Rambam - 3 Chapters a Day

A priest is, however, allowed to become impure from other sources (Hilchot Tumat Ochalin 16:9).

As is appropriate for the violation of a negative commandment. Sefer HaMitzvot (negative commandment 166) and Sefer HaChinuch (mitzvah 263) count this as one of the 613 mitzvot of the Torah.

Covering a corpse with a portion of one’s body creates a “tent,” as it were, and this conveys ritual impurity (Hilchot Tumat Meit 1:10). Similarly, carrying a corpse, even if one does not touch it, coveys ritual impurity (ibid.:6).

E. g., blood that flowed from a corpse, bones from a corpse, a corpse that has decomposed or the like.

See the exegesis of this verse in the Sifri.

See Chapter 2 of those halachot.

See Hilchot Tumat Meit 2:15, based on Numbers 19:16, 18.

The clothes become an av tumah, a source for ritual impurity. Nevertheless, they are not considered as equivalent to the corpse itself. See Hilchot Tumat Meit 5:3, 13; Hilchot Nazirut 7:8.

This refers to a building next to the building where a corpse is located. There is a window or roof connecting the two through which the ritual impurity enters the structure. The Siftei Cohen 372:2 argues with the Rambam’s ruling, maintaining that such ritual impurity is merely Rabbinic in origin. Hence lashes are not given. The Magen Avraham 343:2 justifies the Rambam’s ruling.

Hilchot Tumat Meit, chs. 14-19.

As explained in those chapters, the term ohel, “tent,” is used to describe any roof, shelter, overhang, or any substance that covers both a person and a corpse or portion of a corpse.

See Hilchot Tumat Meit 13:2.

Hilchot Tumat Meit 1:12.

One does, however, become impure through touching or carrying a non-Jewish corpse.

I.e., a corpse.

See Hilchot Bi’at HaMikdash 3:23 which speaks of the prohibition against remaining within the Temple courtyard while impure. There it states that if a person waits in the courtyard for the period which it takes “to kneel, to prostrate oneself face down on the ground and to give thanks to God who is good, whose kindness is everlasting,” he is liable.
The commentaries question: Why should he be lashed? One is not liable for lashes unless one commits a deed in violation of a transgression (Hilchot Sanhedrin 18:2). Here, seemingly, one’s violation is passive.
Among the explanations offered to resolve this difficulty is that since he had the potential to remove himself from ritual impurity and did not do so, he is considered as if he performed a deed to contract ritual impurity (Ritbah, gloss to Makkot 21 a). Others cite the gloss of the Maggid Mishneh to Hilchot Sechirut 13:2 which explains that whenever a transgression usually involves a deed - as a priest usually performs a deed to contract ritual impurity - one is liable for lashes even when one violates the transgression without performing a deed.

For each involves a separate transgression.

I.e., his actions are considered as a single, extended transgression. The Radbaz refers to the difference of opinion mentioned in the notes to Chapter 2, Halachah 15, stating that according to the Rambam, it would appear that although the priest does not receive lashes, he is considered to be violating a prohibition. According to the other view mentioned there, there is no prohibition at all to come into contact with other corpses.

See Hilchot Rotzeach 12:14 which interprets this as a general prohibition, warning a person against. causing a colleague to transgress.

Although he is not himself a priest.

Because of the greater sanctity associated with his position, he is given greater restrictions. He is, however, obligated to observe all the mourning rites for his relatives (Chapter 7, Halachah 6).

Sefer HaMitzvot (negative commandment 167) and Sefer HaChinuch (mitzvah 271) count this as one of the 613 mitzvot of the Torah.

Sefer HaMitzvot (negative commandment 168) and Sefer HaChinuch (mitzvah 270) count this as one of the 613 mitzvot of the Torah.

A High Priest; an ordinary priest, however, would be liable for only one transgression (Radbaz).

As long as the High Priest is in this container, he is not liable, because the container separates him from the corpse and it is as if he is not in the same place. When, however, the top of the container is removed, he is considered to have entered the place where the corpse is located and he becomes impure.
There are some who cite Nazir 43a which states that this is speaking about a situation where the High Priest helped the other person remove the top. Otherwise, the High Priest will not have committed a deed in his violation of these prohibitions. According to the explanations offered in note 16, however, that explanation is not necessary.
See also Hilchot Nazirut 5:18 which cites a similar law applying to a Nazirite and states that he must open the top “with [the Nazirite’s] consent.” For otherwise, the Nazirite - and the High Priest - will become impure because of factors beyond their control.

The Radbaz asks why the Rambam speaks about a High Priest; the same laws would also apply with regard to an ordinary priest. He explains that the Rambam is speaking about the prohibition against entering a place of impurity and that applies only with regard to a High Priest. If he would have spoke about the prohibition against incurring ritual impurity, then this ruling would also be applied to an ordinary priest.

As explained in the notes to Halachah 4, as long as he has ceased contact with a corpse - even though he is still ritually impure - he is liable for entering a shelter where a corpse is located (Radbaz).

We have translated the term according to its practical meaning. Literally, the terms the Rambam uses mean: “A corpse which it is a mitzvah [to bury].” For every Jewish corpse should be buried as soon as possible. Thus if there are no others to tend to it, even a priest or a Nazirite who would ordinarily be forbidden to touch the corpse are under obligation to bury it. Torat Kohanim derives the obligation for a priest to become impure for the sake of such a corpse from the exegesis of Scriptural phrases.

The Turei Zahav 374:1 emphasizes that there must be enough people besides the priest to give the person a proper burial.

Today with the proliferation of cell phones and satellite phones, this halachah is becoming less relevant. For in most instances, it is possible to call to others to tend to the corpse. Also, there are legal restrictions in most countries against burying a corpse oneself and a person is not obligated to place himself in danger by burying an unattended corpse. Needless to say, however, if a priest is not certain that a person is dead, he should approach him and try to offer first aid.

I.e., it continues only for the extent of his vow. Moreover, even if the nazirite took a vow to continue this practice indefinitely, his obligation to avoid a corpse is not an inherent dimension of his being, but an incremental factor. A priest's holiness, by contrast, is inherent to his existence (Radbaz).

See Hilchot K’ lei HaMikdash 4:19 which lists various different levels of holiness among the priests.

The assistant to the High Priest (ibid.:16).

See Hilchot Melachim 7:1.

Although in Hilchot K’lei HaMikdash, loc. cit., the Rambam rules that the priest anointed to lead the army is on a higher level, in this halachah, he relies on Nazir 47a which grants the s’gan precedence. The rationale is that if the High Priest becomes disqualified on Yom Kippur, the s’gan assumes his position.

The head of the Supreme Sanhedrin. See Hilchot Sanhedrin 1:3.

The Jerusalem Talmud (Nazir 7:1) relates that when Rabbi Yehudah HaNasi died, Rabbi Yannai announced: “There is no priesthood today.’’

For it is not befitting for a nasi to be mourned merely by his family and friends. Instead, the entire Jewish people should show him respect. Everyone is considered as if he was his relative. See also Chapter 9, Halachot 2, 6, 12, and 14, which mention other mourning rites undertaken as a token of respect for a nasi.
There are authorities who maintain that this law is not only relevant in the Talmudic era. Tosafot, Ketubot 103b quotes Rabbi Chayim Cohen as stating: “Were I present when Rabbenu Tam died, I would have become impure for his sake.” The Radbaz, however, questions that license. Significantly, the Shulchan Aruch (Yoreh De’ah 374:11) which mentions only the laws which are relevant in the present age, mentions the obligation to become impure for the sake of a nasi.

I.e., they should not eat meat or drink wine until his burial as stated in Chapter 4, Halachah 6.

I.e., women born to the priestly family.

Offspring born to a priest by a woman whom he is forbidden to marry (Hilchot Issurei Bi’ah, Ch. 19). The Radbaz and the Siftei Cohen 373:2 emphasize that this leniency applies only to individuals who are considered challalim by Scriptural Law. One who is, however, considered as a challal according to Rabbinic Law, e.g., a person born to a priest and a woman who performed the rite of chalitzah, must keep these stringencies. For according to Scriptural Law, he is a priest.

Thus excluding challalim who are considered as non-priests with regard to all matters (see Hilchot Issurei Bi’ah 19:10; Hilchot Terumah 6:7; Hilchot Ma’aseh HaKorbanot 11:8).

Yevamot 114a derives this concept from the use of the similar terms emor and vi’amarta by Leviticus 21:1.

I.e., the Jewish community as a whole does not have the obligation to train every child in observance. Instead, the obligation is a personal one, incumbent on the child’s father. See Hilchot Ma’achalot Assurot 17:27-28 where this issue is also discussed.

Sotah 44a explains that this is a Rabbinic decree, enacted to compel priests to keep their distance from corpses lest one accidentally, pass his hand over the corpse or the like. If, however, a barrier is erected around the corpse, this stringency need not be observed [Radbaz; Shulchan Aruch (Yoreh De’ah 371:5)]. In such a situation, he should nevertheless keep a distance of four handbreadths.

The punishment given for the violation of a Rabbinic decree.

A field in which a grave had been located, but which had been plowed over. The Sages forbade a priest from entering such a field for 100 cubits, lest he accidentally step on a small piece of bone from the corpse.

This applies in the era when the laws of ritual impurity were strictly observed in Eretz Yisrael. See Siftei Cohen 369:2.

A mixture of blood, some which was lost before the person passed away and some which drained from his corpse after his passing.

Chapter 2, Halachot 13-16.

For by stepping on a grave, he becomes impure, because he creates an ohel, “shelter,” over the grave. The Radbaz emphasizes that this law applies only when there is no way to enter the cemetery except by walking on the graves. Different rules apply, however, if there is a path through the cemetery. In such an instance, if a priest walks within four cubits of a grave, he receives stripes for rebellious conduct and if he remains more than that distance away, he is not liable at all.

I.e., even priests.

Since there is a handbreadth of space between the top of the coffin and the corpse, the impurity is contained and does not extend beyond the coffin according to Scriptural Law. Our Rabbis, however, ruled that according to Rabbinic Law, one contracts impurity from a coffin (Berachot 19b).

I.e., with the coming of Mashiach.

There is an allusion to this custom in Genesis 46:4 which relates God’s promise to Jacob that Joseph would place his hands over his eyes.

This refers to the taharah procedure. The purpose is to endow the corpse with purity (Perishah, Yoreh De’ah 352).

So that air will not enter the body and cause it to decompose quickly (Hilchot Shabbat 26:20).

So that the pallbearers will not be repelled by the odor of the corpse at the time of burial. The Ramah (Yoreh De’ah 352:4) mentions other customs.

Our translation follows the version of authentic manuscripts of the Mishneh Torah. The standard printed text reads slightly differently.

Mo’ed Kattan 27b states that this practice was initiated by Rabban Gamliel. Although as nasi, he obviously had ample resources, he ordered that his corpse be buried in. a simple linen shroud, because in his day, the burial expenses were becoming more difficult to bear than the person’s death. It had reached the point that people would simply abandon a corpse rather than bury it, because of the great expenses involved.
The Radbaz writes that at his time, this custom was discontinued and it was common for those who had the means to buy expensive shrouds. The rationale is that Ketubot 111b states that in the era of the Resurrection, the dead will arise together with their clothes. Thus clothing the dead in elegant garments is an expression of one’s faith in the coming of that era. We do not worry about the poor, because it has already become customary to bury those who cannot pay for their own funerals at the community’s expense.
The Shulchan Aruch (Yoreh De’ah 352:1) and the Siftei Cohen 352:1 appear to suggest an intermediate position: not using expensive shrouds, but not necessarily overly simple ones either. This is the common practice today.

See Chapter 14, Halachah 25. See also Hilchot Melachim 6:10 which describes the prohibition against destroying useful property.

Note the prohibition against such emulation in Hilchot Avodat Kochavim 11:1.

I.e., rather than use wagons. This concept is derived from the description of Jacob’s funeral procession (Genesis 50:13): “His sons carried him to the land of Canaan.” At present, the custom is to transport a corpse to the cemetery in a hearse and to begin carrying the coffin shortly before the grave.

The Radbaz and the Kessef Mishneh write that this applied only in the Talmudic period when there were specific individuals designated as pallbearers. In the present age, it is customary for everyone to help carry a corpse. Hence if one person is delayed, his place will be taken by another. The Radbaz also explains that it is possible that the prohibition applies only to sandals and not to ordinary shoes.

This reflects the custom, still followed in most places in Eretz Yisrael today, to bury the corpse in the ground without a coffin.

Genesis 3:19 states: “To earth you shall return,” and Ecclesiastes 3:20 states: “Everything is from the earth and everything returns to the earth,” implying that a corpse should be placed in the earth itself. Nevertheless, since there are pores in wood, even while it is in a casket, the corpse is considered as being in contact with the earth. It is, however, preferable for the corpse to be placed in the ground itself [Shulchan Aruch (Yoreh De’ah 362:1)]. It is also customary to make two holes at the bottom of a wooden coffin to allow direct contact with the earth.

As a corollary to this concept, Berachot 64a and Mo’ed Kattan 29a emphasize that this expression should not be used when bidding a living person farewell. Instead, one should say: “Go to peace.”

The verse communicates the prophecy that Abraham will die in tranquillity.

In the Talmudic era, it was customary to place an outline of lime around graves so that people who were ritually pure would not step on them.

Our translation follows the authoritative manuscripts and early printings of the Mishneh Torah. The standard printed texts follow a slightly different version.

Based on the Jerusalem Talmud (Shekalim 2:5), the Kessef Mishneh explains that an ordinary person is remembered by visiting his grave and therefore a tombstone is necessary to mark it. A righteous sage, by contrast, is remembered because of the Torah insights which he developed. There is no need to visit his grave. And hence, a tombstone is unnecessary.
Despite this explanation, it must be emphasized that it is common custom to place tombstones at the graves of the righteous and to go there to pray. Indeed, there is a tombstone placed at the Rambam's own grave in Tiberias.

I.e., a priest is not liable for entering the house. Similarly, a dying man can divorce his wife so that she will not have to undergo chalitzah rites.
With regard to license for a priest to enter the house: the Shulchan Aruch (Yoreh De’ah 370:1) forbids it, but the Ramah permits it.

As indicated by Halachah I and notes, these measures are intended to prevent a corpse from decomposing and producing an unpleasant fragrance and to prepare it for burial.

See Chapter 8, Halachah 3.

Lest the dying person take notice and become aggrieved. This might hasten his death.

For eating in the presence of a corpse could be interpreted as mocking him, implying that one can partake of the pleasures of this world while the corpse cannot (Berachot 17b and commentaries).
We have translated bayit as “house.” For in Talmudic times, homes were often one room structures. The term can also be rendered as “room.” Halachicly, that interpretation is also acceptable.

As is the custom of important personages when they dine.

For while he is allowed to eat, he may not indulge.

To introduce grace with a blessing.

The mourner is considered as being “involved with a mitzvah,” for he is concerned with the burial of his dead. And we follow the principle that a person involved with one mitzvah is not obligated in another.
The Jerusalem Talmud (Berachot 3:1) states that even if a person desires to be stringent with himself and observe the mitzvot, he should be restrained from doing so. It gives two rationales: a) It implies that one is not concerned with mourning for the deceased and thus detracts from his honor; b) It will prevent one from taking the steps to bury the deceased as soon as possible. According to the second rationale, if there are others who are prepared to deal with the deceased’s burial, the mourner himself may go to the synagogue and pray.
The Shulchan Aruch (Orach Chayim 71:1) quotes opinions which forbid a mourner to be stringent upon himself and perform mitzvot if there are others who are dealing with the corpse’s burial and others which allow him this privilege. The Shulchan Aruch HaRav 71:1 and the Mishnah Berurah 71:7 state that a person in this stage of acute mourning should not observe the mitzvot under any circumstance.

When nothing can be done to bury the dead and outward expressions of mourning are forbidden.

For private expressions of mourning are required on the Sabbath. Hence, sexual relations are forbidden (Chapter 10, Halachah 1). Tosafot, Mo’ed Kattan 23b, refers to engaging in sexual relations at the time when one’s dead is not buried as chutzpah, “brazen conduct.”

Lest one become intoxicated. See Chapter 13, Halachah 8.

For an early burial is a measure of respect for the dead.

For one must mourn excessively for one's parents and arranging their funeral hastily shows a lack of respect.

When delaying the burial would cause it to be postponed for an additional day or more, it is considered more of an honor to bury the dead earlier than to prepare a more impressive funeral. In the present age, when corpses are held in refrigerated morgues, there are communities where even on Friday and on the day preceding a festival, funerals are postponed.

See Hilchot Sanhedrin 15:8.

To bring a coffin or shrouds, to enable relatives to come, or to announce his passing in outlying places [Shulchan Aruch. (Yoreh De’ah 357:1)].

I.e., even after the burial of the deceased when the mourner is obligated to perform mitzvot.

Bringing food for the mourners, particularly the seudat havraah (the meal of comfort served directly after the funeral; see Chapter 13, Halachah 7) is a great mitzvah. The Perishah (Yoreh De’ah 378) explains that, at this time, a mourner is overcome by his suffering and will not see to his own needs. Therefore his neighbors are commanded to tend to him.

The Ra’avad protests stating that he never saw a source for this custom. It is not accepted in most communities at present, as stated in Shulchan Aruch (Yoreh De’ah 387:2). See also Chapter 5, Halachot 17-18 and notes.

I.e., during the seven days of shivah.

In the Ashkenazic community, it has become customary to sit on low stools.

These instructions were given at the time of the death of Ezekiel’s wife. “Glory” refers to tefillin as indicated by Targum Yonaton to that verse and Ketubot 6b.

Rashi (Sukkah 25a) explains that when a person girds himself with glory (tefillin), he implies that he is not devastated by his loss.

Although the Rambam speaks of this restriction as applying for the entire day, Rabbenu Asher maintains that it applies only for the first meal eaten after the burial. Shulchan Aruch (Yoreh De’ah 378:1) follows this view.

See Chapter 1, Halachah 1.

The Rambam explains each of these restrictions at length in the halachot which follow.

After the deaths of their brothers. They were given this command in honor of the dedication of the Sanctuary and such conduct was appropriate only at that time.

This also applies during the 30 days of mourning as stated in Chapter 6.

For shaving is forbidden, regardless; see Hilchot Avodat Kochavim, ch. 11.

I.e., even the hair of others (Radbaz).

For having half of one’s hair cut would appear ludicrous.

If one is cutting someone else’s hair and there is another barber in town, one should cease and have the other barber finish the haircut [Kessef Mishneh; Shulchan Aruch (Yoreh De’ah 390:2)].

These reflect Yoav’s instructions to the wise woman of Tekoa. Although she was only feigning mourning, the fact that she followed these practices indicates that they are followed by mourners.

The Shulchan Aruch (Yoreh De’ah 389:3) state that this applies to colored clothes as well. The Shulchan Aruch (loc. cit.:1) also forbids using freshly laundered sheets. Wearing pressed clothes is also forbidden for the 30 days of mourning as stated in Chapter 6.

Similarly, the Shulchan Aruch (Yoreh De’ah 381:1-2) allows one to wash oneself in an ordinary manner to remove filth and to anoint oneself for medicinal purposes. The Radbaz quotes the Jerusalem Talmud (Berachot 2:6) which states that any washing that is not for pleasure is permitted.

The Radbaz quotes Mo’ed Kattan 24a which states that there was a person who engaged in relations during the week of mourning and afterwards, wild pigs tore apart his body.

After the conclusion of the mourning period for their son who died.

This is also forbidden for the 30 days of mourning as stated in Chapter 6.

The Shulchan Aruch (Yoreh De’ah 383:1) states that the restrictions observed when a woman is in the niddah state need not be observed at this time. Although the letter of the law allows this, the Radbaz and many other authorities suggest being stringent.

This refers to an ordinary mourner. If, however, a couple have never engaged in relations - e.g., one of their parents dies directly after their wedding - they may not remain in solitude together [Shulchan Aruch (Yoreh De’ah 383:2)].

The prohibition involves only leather shoes. Shoes from other materials may be worn [Shulchan Aruch (Yoreh De’ah 382:1).]

In the instructions God gave him in connection with his wife's death.

Similarly, a person is allowed to wear shoes if there is a danger of being bitten by scorpions or for other health reasons, e.g., a woman who just gave birth [Shulchan Aruch (loc. cit.:2-3)].

In a city inhabited primarily by gentiles, some authorities grant license to wear one’s shoes until one reaches the Jewish quarter [ibid.:4].

In contrast to the previous halachot which mention prohibitions that can be derived from the literal meaning of the verse, this prohibition is merely hinted at by the verse (Radbaz; Kessef Mishneh).

If the mourner stands to lose a considerable amount (davar ha’avaid) if a transaction is not carried out, leniency may be granted for others to carry out this transaction for him as leniency is granted during chol hamoed [see Hilchot Sh’vitat Yom Tov 7:22; Radbaz; see also Shulchan Aruch (Yoreh De’ah 380:6)].

See Chapter 6, Halachah 2, which explains that this prohibition also applies during the thirty days of sheloshim mourning.

As evident from Chapter 13, Halachah 11, the first three days of mourning are the most intense when the mourner weeps over his dead. If he is forced to work, he will be prevented from weeping (Kessef Mishneh).

And needs to perform this work to earn his livelihood.

The Jerusalem Talmud (Mo’ed Kattan 3:5) states: “May a curse come upon his neighbors who required him to do this,” i.e., who did not provide for his needs.

The Radbaz states that this applies even to a rich woman and even during the first three days of mourning, since it is extremely undesirable for a woman to be idle. See Ketubot 59b.

In his Kessef Mishneh and in his Shulchan Aruch (Yoreh De’ah 380:21), Rav Yosef Caro explains that our Sages sought to prevent public knowledge of the functioning of the partnership. Accordingly, the store must be closed. If, however, it is possible for the other partner to perform activities on behalf of the partnership in private without public knowledge, he may. The profits are then split by the two. If, however, the mourner is a well-known person and hence, any work performed on his behalf will become public knowledge, it is forbidden for his partner to perform work.

The intermediate days of the festival when ordinary work is forbidden, but license is granted to perform work if otherwise, a person will suffer a substantial loss (see Hilchot Sh'vitat Yom Tov 7:1-2).

So that his attention will not be diverted from his mourning (Rabbenu Nissim).

But not his own servants or the members of his household whom he supports [Radbaz; Shulchan Aruch (Yoreh De’ah 380:4).]

For a wage, not merely as a favor for the mourner.

Before olives are pressed, they are left in the sun. First they are exposed on one side and then on the other. If they are not turned over, they will spoil.

To protect the oil placed inside them.

In both these instances, leaving the fabric to soak beyond the desired time will cause it to spoil.

In this halachah, the Rambam speaks about instances that apply in an agricultural society. Similar principles apply with regard to activities fundamental to a commercial society as mentioned in the notes to Halachah 7.

The Hebrew terms used by the Rambam include both sharecroppers who give a fixed percentage of the crops and those who give a fixed amount of produce.

Paying a fixed fee. The Rambam defines the three Hebrew terms used in this halachah in Hilchot Sechirut 8:1-2.

For they are working on their own behalf and not on behalf of the mourner who owns the fields.
The Radbaz and the Kessef Mishneh quote the Ra’avad who explains that this applies even if the rental agreement ended before the beginning of the period. In contrast to the animals or ships mentioned in the second clause, it is common to rent out land. See Shulchan Aruch (Yoreh De’ah 380:11).

Even though they were rented out before the person became a mourner, since the term of the rental agreement was not specified originally, continuing to rent them out considered as "work" and hence, is forbidden.

Employing a profit sharing agreement.

Since they were rented out for a specific time period, during that time period, they are considered as belonging to the renter.

Mo’ed Kattan 11b explains that this refers to a person who works the mourner’s land.

Since the mourner’s ownership of the land is common knowledge, having work performed on the land is considered as if he performed work in public.

Work with materials not connected with landed property, e.g., to sew clothing or to make furniture.

In which instance, one might think there might be room for leniency since he is not being paid specifically for the days of mourning.

For he is not allowed to perform work during the days of mourning.

Lest others think he helped perform the task or hired the person during the days of mourning.

For people at large will not necessarily know that these tasks are being performed, nor will they have reason to associate them with the mourner.
The Kessef Mishneh and the Ramah (Yoreh De’ah 380:18) emphasize that the work must have been contracted out before the period of mourning began.

For litigation, like work, will divert his attention from mourning.

E. g., the defendant or the witnesses are leaving the locale and it will be impossible to prosecute the matter in the future (Radbaz).

Just like a person may appoint an agent to perform his work for him when there is a possibility of loss (Halachah 10), he may appoint an agent to prosecute his claim. Although generally it is undesirable to have an agent prosecute a claim (Hilchot Shluchim 3:5), license is granted in this instance because of the extenuating circumstances.

In the instructions God gave him in connection with his wife’s death. Tosafot, Mo’ed Kattan 21 b associates this prohibition with the fact that Torah study engenders happiness, as Psalms 19:9 states: “The precepts of God are just, bringing gladness to the heart.”
The Radbaz (in his gloss to Halachah 20) asks why in this instance we are required to emulate Ezekiel's example while in all other instances, we are required to conduct ourselves in the opposite manner. He explains that in all instances Ezekiel was given instructions that relaxed his mourning obligations and hence, we do the opposite. Here, he was given instructions that increased his mourning and hence, we certainly must follow them.

Based on Mo’ed Kattan 21a, the source for this halachah, it would appear that the Rambam is referring to the realm of study known as Aggadah, i.e., the homiletic teachings of our Sages.

Torah law.
Tosafot, loc. cit., explains that only Torah subjects that bring happiness are forbidden. The Books of Eichah and Job and similar prophecies of retribution are permitted. Similarly, it is permitted to study the laws of mourning. These concepts are reiterated by Shulchan Aruch (Yoreh De’ah 384:4).

In the Talmudic era, it was not customary for a teacher to deliver a lesson to the people himself. Instead, he would stand before them and speak to a spokesman who would, in turn, communicate the teachings to the people at large. See Hilchot Talmud Torah 4:3.

In Chapter 4, Halachah 9, the Rambam writes that a mourner must sit on an overturned bed. The Radbaz explains that he is not obligated to sit on an overturned bed for all seven days of mourning. The bed must remain overturned, but the person may sit on the ground. As mentioned in the notes to that halachah, at present it is not customary to turn over beds as a sign of mourning.
The Siftei Cohen 387:1 states explicitly that a mourner should sit on the ground itself. It is not sufficient for him to sit on a low stool or cushion. Nevertheless, the common custom is to do the latter. Perhaps the source for leniency is the license granted for a sick or old person to sit on low stools or cushions because it is difficult for them to bear discomfort.

With regard to a rumor that all of King David's sons had been slain.

A low bed or chair with a leather base that is tied to posts by straps that is larger than a bench (the Rambam's Commentary to the Mishnah, Sanhedrin 2:3; Hilchot Nedarim 9:15).

The Shulchan Aruch (Yoreh De’ah 386:1) requires the observance of this practice. The Ramah, however, states that it has not been customary to observe it within the Ashkenazic community, nor is one obligated to do so.

In his translation of the Torah into Aramaic.

As reflected by the gloss of the Radbaz to Chapter 10, Halachah 1, this obligation applies only when sitting alone. When sitting with others, the mourner may uncover his face. This conclusion is quoted by the Shulchan Aruch (Yoreh De’ah 386:1).

As will be explained, the colleague should not greet him. If he does - because he does not know that he is a mourner or because he errs and/or forgets the law, the mourner may respond.

For they are in a state of well-being and composure.

For he has not reached a state of composure (Mo’ed Kattan 21b).

For laughing in a state of mourning will be unseemly in the eyes of the public (Mo’ed Kattan 26b).

As stated in Chapter 6, Halachot 2 and 7, this restriction applies for a month and when one is in mourning for one’s parents, for twelve months.