Kri'at Shema - Chapter Two

One who recites the first verse of Kri'at Shema - i.e., Shema Yisrael... - Berachot 13b mentions several opinions concerning which sections of the Shema require intention. This is dependent on the discussion (See commentary, Halachah 2) regarding the extent of the obligation to read Shema required by the Torah. Rabbi Meir understands intention to be absolutely necessary only for the first verse and this opinion is accepted by the Shulchan Aruch, Orach Chayim 60:5.

without intention - The definition of the term "intention" is the subject of much discussion by the Rabbis.

There is a dispute among the Rishonim regarding whether the performance of commandments requires intention, i.e., must a person have in mind that he is performing the required act in fulfillment of God's command or not? The Rambam (See Hilchot Shofar 2:4 and note Hilchot Chametz U'Matzah 6:4, and the commentary of the Moznaim editions of those Halachot) maintains that it is necessary to have such an intention. This opinion is also supported by Rabbenu Yitchak Alfasi and Rabbenu Asher and is accepted as Halachah by the Shulchan Aruch (Orach Chayim 60:4, 598:8). [The dissenting opinions are held by the Rashba and others.]

However, concerning the first verse of Kri'at Shema, an extra level of concentration is required. In addition to the intent to carry out God's command, the Shema must be read in fear and awe, trembling and trepidation. One accepts upon oneself the kingship of Heaven and proclaims the unity of God. It is unthinkable that at such a time, one would not focus his attention on the words he is uttering, but would rather think of mundane matters. (See Shulchan Aruch HaRav 60:5.)

Each day one should imagine that he is reciting Shema Yisrael for the first time, and not as if he had heard it many times before (Shulchan Aruch, Orach Chayim 61:1,2).

Kri'at Shema contains 248 words (245 of the three sections, plus the three extra words of Ado-nai Elo-heichem Emet repeated upon completion of the third section). This corresponds to the 248 positive commandments in the Torah and the 248 limbs of the human body (Midrash Ne'elam; quoted by the Shulchan Aruch, Orach Chayim 61:3.) Thus, the recitation of the Shema, with its affirmation of God's kingship and Unity, imbues the totality of one's being with these fundamental concepts.

does not fulfill his obligation. - and must therefore recite the Shema again.

[One who recites] the rest without intention fulfills his obligation. - Needless to say, it is not desirable to read the Shema in this manner and, at the outset, one should attempt to read the entire Shema with proper concentration.

Even a person studying Torah in his usual way - i.e., even were he studying these three sections of the Torah.

or proofreading these portions - i.e., he was examining these particular sections in a scroll to ensure their correctness.

at the time of Kri'at Shema fulfills his obligation, provided he concentrates his intention for the first verse - i.e., he must have the unique level of intention that is required for the first verse, as mentioned above.

The Kessef Mishneh explains that intention of any kind is necessary for only the first verse and, afterwards, one could continue studying or proofreading in a normal fashion, provided he reads the words properly. The Magen Avraham also supports this position (Orach Chayim 60:5).

A person may recite [the Shema] as he is - This is based on Hillel's interpretation of the verse "...and when you walk on the way" (Deuteronomy 6:7). (See the commentary on Chapter 1 Halachah 1 for further elucidation.)

whether standing, walking or lying down - Berachot 11a expands the mishnah's teachings in this manner.

or riding an animal - Kiddushin 33b equates riding on the back of an animal with walking.

It is forbidden to recite the Shema while lying face down on the ground or flat on one's back with his face pointing upwards. - Rashi (Berachot 13b) explains that these positions are improper because they imply an attitude of haughtiness which is inappropriate at the time one must accept the yoke of Heaven.

However, one may recite it lying on his side - He should be completely on his side, since Berachot (ibid.) also forbids reciting the Shema while turned slightly over onto one's side, unless extraordinary circumstances prevail, as explained by the Rambam in this halachah.

A particularly obese person who cannot turn over onto his side or a sick person should lean slightly to the side and [then] recite it. - Rabbenu Manoach states that it is forbidden for anyone else to read in such a fashion as mentioned above. They should sit upright in a position evoking awe and fear while reciting the Shema.

A person who is walking on foot must stop for the first verse - in order to concentrate his attention.

Berachot 13b mentions two opinions regarding the extent of the Shema one must recite before he may continue on his way:
that of Rav Yehudah which requires the first two verses of the Shema to be recited standing;
and that of Rabbi Yochanan which requires the entire Shema to be recited in a stationary position.

Rav Yitzchak Alfasi explains that the actual halachah does not follow either of these positions, but rather is in accordance with the view of Rabbi Meir that only the first verse requires absolute intention. (See Halachah 1.)

The Shulchan Aruch, Orach Chayim 63:3 also accepts this decision.

He may recite the rest while walking - for, as stated above, concentrated attention is not an absolute prerequisite for reading these passages.

If one is sleeping, we should disturb him by awakening him until he reads the first verse. - Berachot, op. cit., explains that one unavoidably overcome by sleep after having recited the first verse has fulfilled his obligation. The Kessef Mishneh notes that the majority of the Rishonim hold that this is the case on the condition that he nevertheless manages to recite the rest of the Shema, albeit in a drowsy state.

Thus, our halachah mentions the necessity of alertness for the first verse within the context of the halachot of the intention required to read the Shema. In Halachah 12, the Rambam discusses sleepiness within the context of the need for proper enunciation of the words of the Kri'at Shema. That halachah supports the Kessef Mishneh's position that one fulfills one's obligation only if he also recites the rest of the Shema.

From that point on, if he is overcome by sleep, we are not obligated to disturb him. - A careful reading of the Rambam’s words leads one to support the position of the Kessef Mishneh just mentioned. After the first verse, the Rambam mentions only that we need not disturb the person, but he does not write that we should not awaken him. This could mean that although we are not obligated to disturb him to such an extent that he is aroused to a state of full alertness, we are obligated to awaken him so that he can finish Kri'at Shema before going back to sleep. (See Shulchan Aruch, Orach Chayim 63:5.)

This and the next three halachot pertain to a person involved in other activities when the time to read the Shema arrives.

A person who is involved in work must stop while he recites the whole first section - Rav Yitzchak Alfasi explains that this applies even according to the halachically accepted position of Rabbi Meir, that utmost concentration is necessary for the first verse only. (See the commentary on Halachah 1.)

The obligation to have proper concentration and the necessity that one's recitation of the Shema not appear haphazard are two different halachic requirements.

Artisans - employed by others, whose time, therefore, is not their own. Even so they must interrupt their work in order to recite Kri'at Shema.

[Parenthetically, we can derive an important concept regarding business ethics from this halachah. If there is a question whether an artisan can interrupt his work to fulfill his fundamental religious obligations, surely, he must serve his employer faithfully at other times.]

must also interrupt their work for the first section, in order that their recitation should not be haphazard. - i.e., a casual matter, regarded lightly. See the commentary to Halachah 8.

They may recite the rest while working . - This applies both to a person working for himself as well as to a paid artisan.

Even one standing in a tree or on top of a wall may read [the Shema] where he is, - Despite the obvious difficulties this poses regarding his ability to concentrate, the Rambam allows a worker to remain in the tree or on the wall and recite the Shema.

Rabbenu Manoach holds that only the workers may remain in the tree. In contrast, a foreman who is there to encourage his work force, must descend from the tree and recite it on the ground. The Tur and the Shulchan Aruch, Orach Chayim 63:8 both disagree with this and allow both of them to recite it while in the tree.

reciting the blessings before and after it - The obligation to recite the Shema also includes the obligation to recite its blessings (Kessef Mishneh on Halachah 5).

A person who is studying Torah when the time to recite the Shema arrives should stop to recite the Shema - Shabbat 9b, 11a states that a person should interrupt his Torah study for Kri'at Shema, but not for the Amidah prayers. This refers even to Sages like Rabbi Shimon bar Yochai who would never interrupt their Torah study except to perform mitzvot which could not be performed by others. The acceptance of the yoke of God's kingship in the Shema is fundamentally necessary even for a person with such an all encompassing commitment to Torah.

Similarly, as stated above, Berachot 10b states that the recitation of the Shema at its proper time is preferable to the study of Torah.

with the blessings before and after it. - See the commentary at the end of the previous halachah.

One who is involved in community matters should not stop - The Jerusalem Talmud (Berachot 5:1) equates involvement in community matters to the study of Torah, in terms of granting an exemption from prayer. The Tosefta, (Berachot 1:4) relates:

Rabbi Yehudah says: Once I was following Rabbi Akiva and Rabbi Elazar ben Azariah. The time of Kri'at Shema arrived (but they did not perform the mitzvah). I was under the impression that they felt unable to. They were, however, involved in community matters.

(See also Tosefta Berachot 2:6.)

but rather finishes his work - Berachot 11a derives this concept from the verse "when you walk on your way" (Deuteronomy 6:7). This implies that "on your way," i.e., while you are involved in your activities, you must read the Shema. In contrast, if you are involved in matters of communal import, there is no obligation.

and reads the Shema if there is still time left. - This implies that even were the time of Kri'at Shema to pass without him reciting the Shema, he need not interrupt his activities (Kessef Mishneh).

A person who is eating, is in the bathhouse, is having a haircut, is working with skins - The Mishnah (Shabbat 9b) prohibits one to start eating, have a haircut, work skins, etc., close to the time of the afternoon prayer. However, the Mishnah adds that were one to start doing one of these prohibited actions, he need not stop. The Rambam also applies these principles to Kri'at Shema (Lechem Mishneh). The Ra'avad (based on Sukkah 38a) differs and holds that a person must interrupt his meal in order to read the Shema.

or is involved in court - i.e., if he is one of the judges.

should complete [his task] and recite the Shema afterwards. If he fears that the time for its recitation - There is a question whether the Rambam refers to 6 minutes before sunrise, the optimum time to recite the Shema, or the end of the third hour of the day beyond which one does not fulfill the mitzvah (See Chapter 1, Halachah 11-13). According to other authorities, the latter view would be followed.

will pass, and, [therefore,] stops to recite it, he has acted in a praiseworthy fashion. - i.e., as long as he is able both to complete what he is doing and to recite the Shema before the end of the proper time for Kri'at Shema, he may complete his task.

There is an apparent difficulty with the Rambam's statements. Halachah 5 states that one must interrupt Torah study in order to recite the Shema, and yet, in this halachah, such mundane matters as eating and haircuts are deemed sufficient reasons to postpone Kri'at Shema.

The Kessef Mishneh explains that the study of Torah is interrupted, since, indeed, the recitation of the Shema need not be understood as an interruption at all. Since Kri'at Shema is in itself a section of the Torah, its reading can be likened to the study of Torah. However, in the case of the mundane activities mentioned in our halachah, Kri'at Shema would involve a complete interruption. Therefore, it is not necessary to stop.

A person who immerses in a ritual bath and is able to come up and dress before sunrise, should do so, and [then] recite [the Shema]. - This is based on the Mishnah in Berachot 22b.

If he is afraid that perhaps the sun will rise - as mentioned in Chapter 1, Halachah 11, the optimum time to recite the Shema in the morning is shortly before sunrise.

before he can recite the Shema, - i.e., before he can dress himself and recite the Shema.

he should cover himself with the water in which he stands and recite the Shema. - These statements reinforce the explanation given in the commentary to Chapter 1, Halachah 11, that the recitation of the Shema after sunrise is only allowed after the fact (בדעיבד). Here, the Rambam states that it is preferable to read the Shema while naked in the water, then to get out, dress, and recite after that time has passed.

He should not cover himself with putrid water that has an unpleasant odor - Berachot 24b equates one who recites the Shema in a place with an unpleasant odor to one who has profaned the word of God. One who stops reciting in such a place is praised, and Deuteronomy 32:47 says about him "... in those words, your days will be lengthened". Chapter 3 deals with many halachot regarding the recitation of the Shema in unclean surroundings.

or with water that has been used for soaking flax - In the Hebrew text of the Rambam and in the Mishnah, the term used is מי משרה (water of soaking). This is understood as water used for soaking flax or canvas, which has a bad smell (Rashi, Berachot 25b).

or with water so clean that his nakedness is visible. - Chapter 3, Halachot 16 and 17, explain how it is forbidden to read the Shema in the presence of "nakedness."

However, he may cover himself with murky water that has no unpleasant odor and recite [the Shema] where he is. - See Berachot 25a.

After discussing the intention necessary for Kri'at Shema and the proper reaction when involved in other activities as the time for the recitation of Shema arrives, the Rambam now deals with the halachot regarding the proper recitation of the words themselves. This discussion continues until the end of the chapter.

While reciting the Shema, a person should not gesture with his eyes or lips, or point with his fingers - Yoma 19b distinguishes between the first section of Kri'at Shema and the second in this regard, forbidding these activities only during the recitation of the first section. Indeed, in Halachah 4 which also deals with a "haphazard" recitation of the Shema, the Rambam, himself makes such a distinction.

Indeed, the Lechem Mishneh explains that the Rambam relies on his statements in Halachah 4. Rabbenu Manoach explains that the Rambam did not clarify the matter explicitly lest he cheapen the value of the second section in the eyes of his reader. The Kessef Mishneh adds that although making such gestures in the second section is not as "improper" as during the first, doing so is, nevertheless, prohibited.

in order that his reading not be haphazard. - Rabbi Acha notes ודברת בם ("and you shall speak of them") implies making these words a matter of primary importance, and not regarding them as haphazard (Yoma, op. cit.).

If one were to do this, although he does fulfill his obligation, he has acted improperly. - Yoma ( op. cit.) refers to Isaiah 43:22: "And you have not called upon Me, Jacob," implying that such a casual reading of the Shema is not considered as calling to God.

The Maharsha explains an added implication of the above verse. Rashi, in his commentary to Genesis 46:29, relates that when Jacob was first reunited with Joseph he made no response because he was reciting the Shema at that time. Surely, one who gestures while reading the Shema has certainly not achieved the level of devotion.

One should recite the Shema so that his words are audible to himself. - This is derived from the word Shema - literally "hear" - in the first verse. It implies that one should make audible to himself that which he says (Berachot 15a).

[However, even] if he does not do this, he fulfills his obligation. - The entire latter portion of this halachah is based on Berachot 15a:

One who recites the Shema so that the words are not audible to himself has fulfilled his obligation. Rabbi Yosse says that he has not fulfilled his obligation. If he reads, but does not enunciate clearly: Rabbi Yosse says that he has fulfilled his obligation. Rabbi Yehudah says that he has not.

The Talmud concludes (ibid. 15b) that the halachah is in accordance with the lenient position in both cases - i.e., the anonymous opinion in the first case and Rabbi Yosse in the second.

Rav Yitzchak Alfasi adds that this is only after the fact. A priori (לכתחילה), one must read in such a way as to be audible to himself and enunciate the letters clearly. The Rambam follows this view.

Nevertheless, one must at least mouth the words of Kri'at Shema, even if he does not pronounce them loudly enough that they are audible to himself. Thought is not regarded like speech. (See the commentary on Halachah 3.) Therefore, one who does not even move his lips, but just thinks about the words as he "reads" them, does not fulfill his obligation (Shulchan Aruch, Orach Chayim 62:3).

One must enunciate the letters clearly. - Berachot 15b derives this from the word ולמדתם- "And you shall teach them." It can be divided into two words ולמד תם, implying that your teaching (ולמד) must be תם - perfect.

[However, even] if he does not do this, he fulfills his obligation. - Berachot ibid. notes that if a person reads the Shema with proper enunciation, "Gehinom will be cooled off for him."

How must one enunciate? He must be careful not to pronounce [a letter with] a strong dagesh - a pronunciation mark implying that the syllable should be stressed.

as if there were no dagesh - e.g., were one to say vedivarta vam instead of the proper pronunciation, vedibarta bam (Deuteronomy 6:7).

or [a letter with] no dagesh as if there were one. - e.g., בכל לבבך (Deuteronomy 6:5) bekol lebabcha instead of the proper pronunciation, bechol levavcha.

Nor should one pronounce the silent sheva - e.g., to say bechol levavecha instead of bechol levavcha.

or silence the pronounced sheva. - e.g., to pronounce בכל נפשך (Deuteronomy 6:5) bechol nafshcha instead of bechol nafsh'cha.

Therefore - since one must enunciate every word carefully

one must pause between two words in which the first word ends with the same letter with which the second word begins. - lest the two be heard as a single word.

For example, when reading בכל לבבך (bechol levavcha) (Deuteronomy 6:5), one should pause slightly between בכל (bechol) and לבבך (levavcha).

[One should act] similarly in the cases of (avadtem meheirah) (Deuteronomy 11:17) and (hacanaf p'til) (Numbers 15:38). - Berachot 15b mentions even more cases of problematic words. The Shulchan Aruch, Orach Chayim 61:20 quotes all the examples found in the Talmud. There are other cases in Kri'at Shema where this problem arises, such as veahavta et (Deuteronomy 6:5). In all these cases care must be exercised to separate the words clearly.

It is interesting to note that the Rambam mentions one example from each of the three sections of Kri'at Shema, in order to teach us that enunciation is equally important in all the sections.

One must also pronounce distinctly the zayin of tizkeru (Numbers 15:40) - in order that he not say tiscaru - i.e., in order that he not declare: "you will garner reward." This halachah also applies to the zayin in uz'chartem (Numbers 15:36) (Kessef Mishneh). (See also the Shulchan Aruch, Orach Chayim 61:17.)

One should sufficiently elongate the dalet in echad (Deuteronomy 6:4) in order to proclaim God's sovereignty over the Heavens and the Earth and all four directions. The chet in echad (ibid.) should not be shortened - Berachot 13b relates:

Sumkos says: Anyone who lengthens the pronunciation of echad, his days and years are lengthened.
Rav Acha bar Ya'akov understands that to refer to the dalet [of Echad]. Rav Ashi says that this is on condition that he not shorten the chet.
Rav Yirmiah was sitting before Rav Chiyyah bar Abba and noticed that he severely lengthened [his dalet]. He said to him that once he had proclaimed God, King above and below and to the four directions of the Heavens, he need not continue [to prolong the dalet].

The Maharsha mentions that the chet (numerical value of eight) corresponds to the Earth and the seven levels of Heaven, and the dalet (numerical value of four) corresponds to the four directions.

so that the word sounds like ee-chad. - If one pronounces a long aleph and a short chet, he will say something that sounds like ee-chad (not one) - i.e., he would seem to be proclaiming exactly the opposite of echad. The Shulchan Aruch, Orach Chayim 61 records more halachot regarding the proper way of reciting the Shema.

It must be emphasized that the elongation of the dalet and the chet should not distort the proper pronunciation of the word.

A person may recite the Shema in any language he understands. - Berachot 13a records a disagreement between Rabbi Yehudah Hanasi, who holds that the Shema must be read as it is - i.e., in lashon hakodesh - and the Sages, who hold that it may be recited in any language. The latter explain that the word Shema - literally, "hear," - indicates the acceptability of any language that one hears - i.e., understands.

One who recites in a foreign language must be as scrupulous in his enunciation as if he were reciting it in the Holy Tongue - i.e., although a person is allowed to read the Shema in a foreign language, he must still fulfill all the halachic requirements of enunciation, and, therefore, careful translation, as prescribed in Halachah 9 (Kessef Mishneh).

The Ra'avad disagrees with the Rambam and prohibits one from reading the Shema in a foreign language. Since any translation is a commentary, he feels that it is impossible to read with the necessary care. The Shulchan Aruch, Orach Chayim 62:2 quotes the Rambam's opinion as halachah.

Nevertheless, the Mishnah Berurah (62:3) points out that although the halachah is indeed that one may recite the Shema, grace after meals, the silent Amidah, and Kiddush on Shabbat in any language, at present, it is highly preferable to say them all in Hebrew. This is even the case for someone who does not understand Hebrew since a proper translation is very difficult, and the true meaning of the prayers will be lost. He points out that certain words (e.g., totafot) are indeed impossible to translate.

One who reads [the Shema] out of order does not fulfill his obligation. This refers to the order of the verses. - The Mishnah (Berachot 15a) states that one who recites the Shema out of order does not fulfill his obligation. The Rambam understands this to refer only to placing verse 2 before verse 1, but not to placing section 2 before section 1, as he states in the continuation of this halacha.

However, were one to reverse the order of the sections, - described in Chapter 1, Halachah 2

even though it is not permitted - for the order established by our Sages should be followed

I hold - This expression implies that this is the Rambam's opinion although he has no definite support for it from our Sages' teachings.

that he does fulfill his obligation, since these sections are not sequential in the Torah. - i.e., the sections do not appear in the Shema in the same order as they are in the Torah itself.

To recite a verse and then repeat it again is improper. One who reads a word and then repeats it, such as one who recites Shema, Shema, should be silenced. - Berachot 33b distinguishes between one who repeats a whole verse and one who repeats the word Shema, as the Rambam discusses immediately after this.

A person who repeats a verse has acted improperly, but is not silenced. - Rashi explains that, although he has acted frivolously and has seemingly scorned the verse, he has not indicated the existence of two rulers with such a reading. In contrast, the repetition of Shema [or Modim (We thank You) - the examples cited explicitly in the Mishnah - appears to indicate that one is paying respect to two kings, 18וóח.

Rabbi Moshe Feinstein points out (Iggerot Moshe, Orach Chayim, Vol. II, Responsa 22) that even in the course of singing prayers, one should not repeat words as cantors are prone to do, even though it does not constitute an interruption per se.

If one reads intermittently, - i.e., he recites part of the Shema and then stops, and then continues reciting, and stops again, etc.

he fulfills his obligation even if he pauses between each reading an amount of time sufficient to complete the entire Kri'at Shema. - This halachah is mentioned with regard to the reading of Megillat Esther on Purim in the Mishnah in Megillah 17a. In his commentary on that Mishnah, the Rambam explains that the one who reads intermittently fulfills his obligation even if he pauses long enough to finish the whole Megillah.

Berachot 24b applies that halachah not only to the reading of the Megillah, which is a Rabbinic ordinance, but also to the recitation of the Shema, which is a Torah obligation. See also Hilchot Shofar 3:5.

The Shulchan Aruch, Orach Chayim 65:1 quotes the Rambam's statements as halachah. The Ramah adds, however, that were one to be unavoidably detained during the recitation of the Shema for a period long enough to finish the entire Kri'at Shema, he must recite it again. Such an interruption is considered significant, since even if he had wanted to finish the Shema, he would have been unable to do so.

The Magen Avraham points out that the Ramah's position would apply only in the case that one were unavoidably detained by the need to relieve himself, or that he suddenly found himself in a place unfit for the recitation of Kri'at Shema. (The halachot concerning these laws are discussed in Chapter 3.)

This refers to the one who recites it in order. - as required by the previous halachah.

If one recites it while drowsy - i.e., not fully awake, but not fast asleep - he fulfills his obligation - See Berachot 13b.

as long as he was fully awake while reciting the first verse. - i.e., in order that he recite the first verse with the intense concentration required by Halachah 3.

One who is unsure whether or not he recited the Shema - Berachot 21a records a disagreement between Rabbi Yehudah and Rabbi Elazar. Rabbi Yehudah says that one who is doubtful regarding whether or not he recited the Shema need not read it again, since Kri'at Shema is a Rabbinical ordinance and we follow the rule a doubt in a Rabbinical ordinance leads to a lenient response.

Rabbi Elazar says that he must recite the Shema in such a situation of doubt because Kri'at Shema is a Torah obligation. Therefore, the principle - ספק דאורייתא לחומרא [a doubt regarding a Torah Law leads to a strict response] - should be followed.

Rabbenu Yitzchak Alfasi and Rabbenu Asher also follow Rabbi Elazar's opinion.

should recite it with the blessings before and after it. - The Rashba in Responsum 320 explains that although the blessings are of Rabbinic origin and, therefore, we should not require one to say them in a situation of doubt (see above, לקולא ספק דרבנן), the proper recitation of the Shema is inseparable from its blessings. Therefore, since we obligate one in doubt to recite the Shema, this entails the recitation of the Shema in its normal fashion - i.e., with its blessings. (See Kessef Mishneh.)

However, if he is sure that he recited the Shema but is in doubt regarding whether he recited the blessings before and after it, he need not recite the blessings again. - Since he has definitely fulfilled the Torah obligation of Kri'at Shema, we invoke the aforementioned rule of לקולא ספק דרבנן with regard to the blessings, which alone are of Rabbinic origin. (See Hilchot Berachot 8:12.)

A person who made a mistake while reciting [the Shema] - i.e., if one skipped over or mispronounced a word or verse

should return to the point of his mistake. - and then continue to read in order, from that verse until the end of Kri'at Shema, in accordance with Halachah 11 in this chapter. See Tosefta, Berachot 2:4.

If one becomes confused and forgets which section he has just completed - i.e., finding himself at a point where it is natural to pause (e.g., between the first section and the second), he becomes confused and forgets exactly what he has finished saying and where he must resume reading.

he should return to the first section - i.e., "And you shall love God, your Lord" (Deuteronomy 6:5) - Berachot 16a states that when one errs in the middle of a section, he returns to the beginning of the section. Were he to become confused between sections, he returns to the first section.

Rashi explains that returning to the first section means to the pause between the first two sections, i.e., one would begin reading from ViHayah Im Shamoa, the second section in Kri'at Shema. The Tur, Orach Chayim 64 also explains the halachah in this fashion.

The Rambam, however, understands that the Gemara obligates one to return to the beginning of the first section. The Beit Yosef explains that both Rashi and the Rambam agree that one must return to the point of the first pause in Kri'at Shema. The Rambam, however, holds that the first pause one makes while reading the Shema is not between the first two sections. Rather, it is after the recitation of ברוך שם כבוד מלכותו לעולם ועד. This signifies the transition between one's acceptance of the kingship of Heaven and the beginning of the recitation of the Shema.

The Shulchan Aruch, Orach Chayim 61:14 states the halachah that one must pause between ברוך שם and ואהבת. However, its decision regarding the law under discussion (ibid. 64:3) reflects Rashi's position.

A person who errs in the middle of a section, but is unaware of where he paused - See the commentary on the previous halachah which discusses this expression.

should return to the beginning of that section. - This is so only if he is completely unaware of where he erred. However, were he to be absolutely sure that he recited part of a particular section, he should start reciting again from after that point (Kessef Mishneh).

One who recited (uch'tavtam) - This halachah is found in the continuation of Berachot 16a, quoted above.

but does not know whether he recited uch'tavtam of [the section of] "Shema" - i.e., of the first section, which begins with Shema Yisrael.

or of [the section of] ViHayah Im Shamoa, (And if you will listen), - i.e., the second section of Kri'at Shema, which begins with these words.

should return to uch'tavtam of "Shema." - In their commentary to the Shulchan Aruch, Orach Chayim 64:4, both the Taz and the Magen Avraham explain that this problem does not arise with the word וקשרתם "And you shall bind," which also appears in both of the first two sections of Kri'at Shema.

In the first section, this word is written with a kamatz וקשרתם (And you [singular] shall bind them), whereas in the second section it is written with a segol וקשרתם (And you [plural] shall bind...)."

However, if his doubt arises only after having recited למען ירבו ימיכם (In order that your days be multiplied, Deuteronomy 11:21), he need not return, because [we assume] he has recited in accordance with the natural pattern of his speech. - i.e., we assume he recited למען in its proper place, at the end of the second section of Shema.

[The following rules apply when] one encounters other people or is approached by them while reciting the Shema. - Having discussed in the previous halachot the proper reaction to unintentional interruptions in Kri'at Shema, the Rambam now discusses when one must purposefully interrupt his reading of the Shema in order to greet people or respond to their greetings.

These halachot are based on the Mishnah (Berachot 13a):

"Between sections, one may initiate greetings out of respect, and respond. In the middle [of a section], one may initiate greetings out of fear, and respond," these are the words of Rabbi Meir.
Rabbi Yehudah says: "In the middle [of a section] one may initiate contact out of respect, and respond out of fear. Between sections, one may initiate out of respect and respond to anyone's greeting."

If he is between sections, - This term is defined in Halachah 17.

he should stop and greet those he is obligated to honor - i.e., he may initiate the contact. This follows Rabbi Yehudah's position in the Mishnah quoted above.

e.g., his father, - The Rambam explains the term mipnai hakavod (out of respect) used in the Mishnah as referring to those one is obligated to honor according to Torah Law; i.e., one's parents in response to the command "Honor your father and your mother" (Exodus 20:12)...

his teacher - i.e., one who taught him Torah. Hilchot Talmud Torah 5:1 states:

Just as a person is commanded to honor his father and fear him, so too, is he obligated to honor and fear his teacher. Indeed, his teacher deserves more than his father. His father brought him into the life of this world, while his teacher... brings him to the life of the world to come.

or anyone greater than he in learning. - Hilchot Talmud Torah 6:1 states:

It is a mitzvah to glorify any Torah Sage even though he is not one's teacher.

If one is in the middle [of a section], he may stop - This applies even when one is in the middle of a verse (Jerusalem Talmud, mentioned by Rabbenu Asher.)

Rabbenu Manoach explains this idea. After making an interruption, one should continue reading where he left off only when the break does not entail the interruption of a single idea. However, when a person is forced to make an interruption after stating only half of an idea, he should repeat the whole verse after the completion of his greeting lest he create a misconception.

In the middle of the verses, שמע ישראל or Baruch Shem Kavod…, one may not interrupt at any time unless one's life is in danger (Shulchan Aruch, Orach Chayim 66:1).

and initiate an exchange of greetings only with someone of whom he is afraid - e.g., a king or tyrant. - The term מפני היראה (out of fear) used in the abovementioned Mishnah refers to a king or tyrant - i.e., someone of whom one is physically afraid.

Rashi explains fear as referring to someone who one is afraid will kill him. Rabbenu Asher takes issue with Rashi's explanation of fear. He points out that it is unnecessary for the Mishnah to inform us that in the case of פיקוח נפש (a life-threatening situation), one may interrupt Kri'at Shema. Even violation of the Shabbat is permitted in such instances.

Therefore, Rabbenu Asher explains "out of fear" as referring to one's father or rabbi: איש את אימו ואת אביו תיראו (Every person must revere his mother and father) (Leviticus 19:3). We also learn in Pirkei Avot 4:12 and Pesachim 108a that the fear of one's rabbi is similar to the fear of Heaven. See also Hilchot Talmud Torah 5:1.

The Shulchan Aruch, Orach Chayim 66:1 accepts Rashi's position regarding honor and Rabbenu Asher's interpretation of fear. He also mentions the Rambam's understanding of "out of fear," as referring to a king or tyrant - this refers to one who is likely to cause pain or sorrow (Kessef Mishneh).

However, he may return the greetings of those he is obligated to honor - e.g., his father or his teacher. - See the commentary on the previous halachah.

The Mishnah Berurah, Orach Chayim 66:1 explains that at present, one should never greet [or return greetings of] anyone during Kri'at Shema, or even during פסוקי דזמרא, the verses of praise that precede Kri'at Shema and its blessings, unless it is clear that such a person will be insulted. Since people do not expect one to interrupt Kri'at Shema in order to greet them, such an insult is extremely rare indeed.

One should, however, interrupt at any point [except in the middle of the verses שמע ישראל and ברוך שם כבוד] in order to respond to Kaddish (יהא שמיה רבא), Kedushah (קדוש קדוש קדוש), Barchu and Modim. (See Shulchan Aruch, Orach Chayim 66:3, the Mishnah Berurah there and Shulchan Aruch HaRav, Orach Chayim 66:2.)

In his responsa, the Rambam also forbids the inclusion of hymns within the blessings [as is Ashkenazic custom on festivals], considering them as an interruption.

These are the intervals between the sections: between the first blessing and the second; between the second [blessing] and "Shema" - This decision is based on the principle that the blessings before the Shema - though necessary to develop the meditative consciousness necessary for the correct intention during Shema - are not considered as directly related to the Shema itself.

Accordingly, though it is forbidden to make an interruption between the recitation of a blessing before a mitzvah and the actual fulfillment of the mitzvah, these interruptions are permitted between the blessings before the Shema and the Shema. Some communities maintain that the blessings before the Shema are similar to the blessings before other mitzvot and do not allow such interruptions.

between the first and second sections of Kri'at Shema; between the second and third sections of Kri'at Shema. Between these sections, one initiates an exchange with one whom it is his duty to honor and responds to the greetings of anyone. - as explained above in Halachah 15.

However, the interval between the end of the third section of Kri'at Shema and [the paragraph beginning with] Emet v'yatziv is considered the middle of a section, - Berachot 14b explains the significance of the proximity of the end of Kri'at Shema, א-להיכם אני ה', to the word Emet. This is based on a verse in Jeremiah 10:10 א-להיכם אמת ‘ה and proclaims that "God, your Lord, is true." Thus, these words do not represent a break between sections, but rather a continuum.

and one may interrupt only to greet one of whom one is afraid, or to respond to the greetings of someone one is obligated to honor. - as explained in the previous halachah.