Rambam - 1 Chapter a Day

Sefer HaMitzvot (positive commandment 99) and Sefer HaChinuch (mitzvah 9) count this as one of the 613 mitzvot of the Torah.

Halachah 2 describes the nature of the destruction required.

There is a deeper dimension to the words chosen by the Rambam. The Minchat Chinuch (mitzvah 9) questions whether the mitzvah of destroying chametz is to destroy the chametz itselfor remove it from our possession—i.e., an active deed—or is it merely to ensure that we possess no chametz. Thus, this mitzvah, like the positive commandment of resting on the Sabbath, can be fulfilled without making any active effort.
The mitzvah to destroy chametz begins at midday on the fourteenth, when chametz becomes forbidden. Thus, the Rambam’s statement that the destruction of chametz must be performed before chametz becomes forbidden, and his description of it as nullification (Halachah 2), reveal that he follows the second interpretation. At the moment the mitzvah begins to apply, the person does not perform any activity. Nevertheless, he fulfills the mitzvah, because there is no chametz. within his possession.

the mitzvah to destroy chametz also applies to chametz discovered throughout the holiday. However, at that time, the chametz must actually be destroyed. (See Halachah 3:11.)

Pesachim 4b

The Talmud explains that the word,ןושאר though generally, translated as “the first,” can also be rendered “before.” For example, in Job 15:7, דלות םדא ןושארה is translated as: “Were you born before Adam?”

that “the first day” ref ers to the f ourteenth of Nisan, rather than the first day of the holiday.

he prohibition mentioned in this verse is also considered as one of the Torah’s 613 mitzvot in its own right. lt is described by the Rambam in Hilchot Korban Pesach 1:5. Since

the mitzvah to destroy chametz must begin beforehand. Thus, quoting this verse serves two purposes:
a) supporting the principle that ןושאר also means before;
b) clarifying when on the fourteenth of Nisan the mitzvah must be fulfilled: before midday (Kessef Mishneh).

The Kessef Mishneh quotes a different version of the text:
What is the destruction to which the Torah refers? to remove all chametz known to one from his property. [The chametz] which is unknown should be nullified...
This version implies that, according to Torah as well as Rabbinic law (See Halachah 2), we must rid our homes of all chametz of whose existence we are conscious; its nullification is not sufficient.
Nevertheless, the Kessef Mishneh brings a number of proofs from the Talmud and also quotes other commentaries of the Rambam, which maintain that the published text is correct and that the nullification of chametz is sufficient according to Torah law. He also quotes Hilchot Berachot 11:15, which emphasizes that “from the moment a person resolves in his heart to nullify it, the mitzvah of destroying [chametz] is fulfilled.”
In the Kuntres Hashlemah, the Tzafnat Paneach contrasts the nullification of chametz to that of avodah zarah (false gods), in which thought is not sufficient and deed is necessary. He explains that the prohibition of avodah zarah affects the very essence of the article. Hence, an act is required. In contrast, the prohibition against chametz does not affect the essence of the food. (Therefore, according to Torah law, it is permitted to be used after the holiday; see Commentary, Halachah 1:4.) Hence, one’s ownership can be nullified by thought alone.

The Rambam describes the more practical aspects of the nullification of chametz in Chapter 3, Halachot 7-10. There, he requires a person to make a formal statement nullifying his chametz. That declaration is a Rabbinic requirement. According to the Torah itself, a firm resolve is sufficient, and no statement is necessary (Binyan Shlomo).

doing so removes his legal ownership over the chametz.

If a person nullifies chametz within his heart and genuinely does not consider it as belonging to him, Torah law does not obligate him for the possession of chametz even if large quantities of it are found within his home.

As explained in the previous halachah, according to the Torah, chametz may be within a person’s property as long as he declared it ownerless. Nevertheless, the Sages forbade such practices and required all chametz סtbe removed from one’s property.
Two reasons are given for this decree:
a) The nullification of chametz is dependent on the feelings of a person’s heart. A person may possibly have difficulty totally removing all thoughts ofownership over the chametz from his heart (Rabbenu Nissim, Pesachim 2a).
b) In contrast to other prohibited substances, chametz is used throughout the year. Thus, were he allowed to leave chametz within his property, he might accidentally forget about the prohibition and eat it on Pesach (Tosefot, Pesachim 2a).
In addition to the restriction against possessing chametz, the Sages further expanded the scope of

to destroy chametz so that it

It must be emphasized that the obligation to search for chametz is Rabbinic in nature only when a person nullifies his chametz when required. Otherwise, the obligation stems from the Torah, for the prohibitions against possessing chametz and the commandment to destroy it require such a search. The Tzafnat Paneach quotes a number of examples that demonstrate how the existence of a Torah commandment obligates a person to check and search to see that it is being fulfilled correctly.

as clarified in Halachah 6, the obligation to search applies only to those holes and crevices in which chametz is usually placed.

The destruction of chametz at night refers to the statement ארימח,לכ in which we nullify all the chametz of whose possession we are unaware. The chametz that we know about is either eaten or destroyed the next morning.

i.e., the night between the thirteenth and f ourteenth of Nisan.

in contrast to the day of the f ourteenth, when the prohibition against possessing chametz begins (Pesachim 4a).

while during the day people are occupied outside their homes.

during the day, its light would not be as eff ective.

Rabbenu Yonah allows a person to continue a study session on the night of the fourteenth if the session began while it was still day. Rav Yosef Karo accepts his opinion, but the Ramah does not. However, the Taz explains that leniencies may be made for public study sessions. Shulchan Aruch HaRav and the Mishnah Berurah go further and allow public study sessions even after nightfall, provided the subject matter is not overly involving.

half an hour before nightfall (Magen Avraham, Orach Chayim 431 :3).

The Maggid Mishneh mentions that it is also improper to begin a meal at this time. The Shulchan Aruch (Orach Chayim 431 :2) also prohibits beginning work. Communal prayer is allowed.

There are two reasons for the preference in carrying out the search in the beginning of the night:
a) it is appropriate to carry out a mitzvah as soon as possible;
b) at the beginning of the night, there is still some daylight left, which will facilitate the search (Ra’avad, Commentary on the Rif).

If one searches by day; i.e., either one forgot to search on the night of the thirteenth and had to carry out the search the following day. Alternatively, one decided to search for chametz before the fourteenth of Nisan with the intention of keeping the room chametz-free afterwards (Jerusalem Talmud, Pesachim 1:1). The light of the sun is insufficient to check indoor areas carefully.

Pesachim 8a explains that a person will be scared to placed a torch close enough to check small holes and crevices carefully lest he start a fire.

lt is customary to use a candle made from beeswax.

a room with three walls and the f ourth side open.

Pesachim 8a states that the same principle applies to the area. directly under an aperture in the roof. The Magen Avraham (Orach Chayim 433:4) also applies this principle to the area directly opposite an open window.

The Rambam’s choice of phraseology clearly implies that it is not desirable to do so. Rather, even a porch should be checked at night by candlelight. Other authorities question this perspective, but it is accepted as halachah by the Shulchan Aruch (Orach Chayim 433:1).

Pesachim 8a states “a courtyard need not be searched.” The Rambam adds the words “the middle” out of fear that the birds will not eat the chametz in the cracks and holes clos·e to the wall. In this case as well, though other authorities are more lenient, the Shulchan Aruch (ibid. 433:6) quotes the Rambam’s opinion.

The Shulchan Aruch (Orach Chayim 433:4) applies the same principle to protrusions extending from a wall.

neither very high or low, see the f ollowing halachah.

In previous generations, the walls of the homes were very thick and large holes would frequently be used f or storage.

for both may use it.

As mentioned in Halachah 2, according to Torah law, the nullification of chametz is sufficient.

see the Jew looking intently through the hole by candlelight and

This might motivate him to harm the Jew. The Sages did not require a Jew to endanger himself to fulfill their decrees.

The Kessef Mishneh (and similarly, the Taz) require the Jew to check the hole for chametz by day.

This is a major principle governing the search for chametz. The Sages only obligated a search where it was likely that chametz might be found. Therefore, they did not require a person to search places into which he did not bring chametz. Nevertheless, places where babies might have brought chametz must be searched, even though adults might not necessarily bring chametz there.

those above a person’s reach (Shulchan Aruch, Orach Chayim 433:4)

Below three handbreadths high (ibid.). The Magen Avraham (433:8) emphasizes that if children are found at home, these lower holes must also be searched.

This halachah continues the final clause of the previous one, listing a number of places into Which chametz is generally not brought.

The commentaries explain that this refers to slanted roofs.

Rashi, Pesachim 8a, explains that most likely, the animals and the chickens will eat any chametz brought there. Nevertheless, the Shulchan Aruch (ibid. 433:6) qualifies this leniency explaining that it does not apply when a person definitely knows that chametz was brought into these premises one month before Pesach. (See Magen Avraham; the Makor Chayim brings a more lenient opinion.) In such an instance, he must search the premises on the night of the thirteenth by candlelight.

Hence, there is little possibility that chametz was brought there.

Small fish may be taken out during the course of a meal. However, generally, a person will take large fish to prepare only before a meal and not in the midst of eating.

In all these cases, the Sages regarded it likely that a person would get up in the middle of a meal while holding chametz in his hand to bring supplies from these storage rooms. Hence, they required such premises to be searched.

On the surface, these holes were mentioned in the previous halachah, and their mention here is redundant.

Thus, unless a person knows otherwise, he must act under the presumption that he brought chametz into these premises.

To be used the following morning.

In this instance as well, there is an obvious reason for the suspicion that chametz has been brought into the home.

for mice do not generally crumble food. (See the following halachah.)

and accidentally ignored, and the mouse deposited the bread it was carrying elsewhere.

Though some authorities do not require a second search when the bread was small and most probably eaten by the mouse, the Shulchan Aruch HaRav and the Mishnah Berurah (Orach Chayim 438) do not accept this leniency.

The Shulchan Aruch (Orach Chayim 438:1) quotes this opinion as halachah. The Magen Avraham (based on the Tur) is more lenient. Rather than require that the entire house be searched, he maintains that searching the room that the mouse entered is sufficient.

even if it was no longer whole

He must be able to recognize this as the bread seen in the mouse’s mouth

and may presume that the mouse ate the rest of the bread.

checked for chametz

The Magen Avraham (Orach Chayim 438:3) explains that if the child is intelligent enough to reply to questions, we should ask him what he did with the chametz and we may depend upon his reply.

Tosefot (Pesachim 10b) require a second search if the amount of crumbs does not equal the quantity of the original bread. The Shulchan Aruch HaRav and the Mishnah Berurah favor the Rambam’s opinion only when the person has nullified his ownership over his chametz. If not, the search takes on the seriousness of a Torah commandment. Hence, it must be repeated.

Hence, the difference between this and the previous halachah.

and the principles mentioned in the previous halachah apply.

For example, after the search for chametz, a person will still have some chametz in his property for use the following morning. However, he may already bring out his Passover matzot.

The Mishnah Berurah emphasizes that this decision applies only when we actually saw the mouse take from the piles. lf no one saw the mouse, the ruling mentioned in the last clause of the following halachah applies.

for chametz

as if it were definitely chametz, as prescribed in Halachah 8.

the permitted and forbidden substances

The probability that the mouse took from the matzot is considered no greater than the probability that he took from the chametz.
This is a classic Talmudic case. Pesachim 9b draws a parallel to the following passage:
Nine butcher shops which all sell ritually slaughtered meat and one which sells meat which has not been slaughtered properly: should a person take meat from one of them without knowing from which he took (i.e., without knowing whether he purchased kosher or non-kosher meat), he must consider [the meat] forbidden because of the doubt involved.
In both cases, the permitted and f orbidden substances remain in one place, and their existence is theref ore considered as fixed.)עובק (In such instances, the fact that there is a much ·higher probability that the article in question was taken from the permitted substances is not considered significant, and the more stringent perspective is taken. See also Hilchot Ma’achalot Assurot 8:11.
Nevertheless, the Ra’avad and other authorities take issue with this halachah, explaining that the Talmud only made such a statement when a person has not nullified his chametz, and the responsibility to search the house stems from the Torah itself. However, if the person already nullified his chametz, the search is only a Rabbinic obligation. Hence, it should be judged more leniently.
The Maggid Mishneh explains that even though leniencies may generally be taken when doubts arise concerning Rabbinic obligations, the search f or chametz is an exception. The entire obligation was instituted even when there was no definite knowledge that chametz existed. Hence, even in this case, a search must be made.
Though the Shulchan Aruch (Orach Chayim 439:1) accepts the Rambam’s opinion, the Ramah and the other Ashkenazic authorities make the following qualification: If the person had already nullified his chametz and if the bread was small enough f or. the mouse to have eaten it entirely, a second search is not required.

In such an instance, we presume that the mouse holding the chametz entered the unchecked house, and the mouse holding the matzah entered the checked house. Comparable decisions are found in Hilchot Terumah 13:14, Hilchot lssurei Biyah 9:29 and Hilchot Mikvaot 10:3.
Pesachim 10a emphasizes that this leniency is only rendered because once a person has nullified ownership over his chametz, the search is only a question of Rabbinic law. The Shulchan Aruch HaRav (Orach Chayim 4.39:4) agrees to this principle, but offers an addition leniency: Even if the owner did not nullify his chametz, a second search is not required when the bread the mouse was holding is small enough to be eaten at once.

Each of the homes is judged individually. Since we do not definitely know that chametz was not brought into either of the homes, we need not change our original presumption and consider each one as free of chametz.
Hilchot Sha’ar Avot HaTum’ah 19:2 mentions a similar case, but reaches a more stringent conclusion. Leniency is only offered when the two people in question approach the Rabbis separately. If they come together, the case is judged more severely.
The Maggid Mishneh and the Kessef Mishneh both note this matter and explain that since the search for chametz is a question of Rabbinic law, greater leniency can be taken. Nevertheless, the Ramah (Orach Chayim 439:2) and other Ashkenazic authorities do not accept this decision and require a second search, should the owners of both homes approach the court together.

Pesachim 10a compares this to a case in which a corpse was presumed to be found in a field. Though Rabbi Meir maintains that the field is considered ritually impure until the corpse is found, the halachah follows the Sages, who maintain that all that is necessary is to carry out a thorough search. The Shulchan Aruch HaRav (Orach Chayim 439:6) states that this law applies even when the owner of the house had not nullified his chametz, and the search is required by Torah law.

we presume that this was the bread the mouse had taken. Pesachim 10a compares this to a case where a field was suspected to contain a grave; the field was searched, and a grave discovered. Though Rabbi Shimon ben Gamliel requires the entire field to be searched, Rabbi Yehudah HaNasi maintains that no further search must be made.
The Shulchan Aruch HaRav (ibid.) emphasizes that this leniency should only be followed when the owner of the house has nullified or can still nullify the ownership over his chametz. Otherwise, he must thoroughly search the entire house.

The passage from Pesachim 9b concerning the ten butcher shops quoted in the commentary on the previous halachah, continues:[If meat from these shops] is found, follow the majority.
The principle of עובק—judging the permitted and forbidden substances as if they were equal—applies only when the doubt concerning the identity of the substance arises in the place where the presence of the forbidden substance has become fixed. Thus, since the meat has become separated) שריפ (from its original place, this principle no longer applies and, as in most cases of mixtures, the decision depends on whether there is a greater number of kosher or non-kosher stores.
Similarly, in the case at hand: Since the loaf became separated from the piles before being taken by the mouse, there is no question of a prohibited substance having a fixed identity.)עובק (Hence, we follow the majority, and thus do not require a further search. The Shulchan Aruch HaRav and the Mishnah Berurah emphasize that this leniency applies even if the owner of the house had not nullified the ownership over his chametz.

The Kessef Mishneh emphasizes that this is a complete thought in its own right.

According to the Kessef Mishneh, this statement applies only to the final instance mentioned in the halachah as explained.

Pesachim 10b explains that the Sages felt that it was likely that the chametz discovered was not the chametz lost. Rather, diff erent chametz was placed in the other corner, and the first chametz, deposited elsewhere throughout the house. Hence, a new search is required (See also Hilchot Mitamei Mishkav U’Moshav 12:16.)
The Shulchan Aruch HaRav (Orach Chayim 439:9) states that if the same amount of chametz that was lost is f ound there is no need to search further if the owner had already nullified the ownership over his chametz. The Mishnah Berurah grants an even greater leniency and frees the owner of the necessity to search, without placing any qualifications on the chametz discovered, as long as he has nullified his chametz.

Pesachim 10a compares this to the following case: “A person put aside 100 dinars of money designated as ma’aser sheni (the second tithe, to be used only to purchase food in Jerusalem) and discovered two hundred.”
In Hilchot Ma’aser Sheni 6:3, the Rambam declares that none of the money is considered as ma’aser sheni. In both instances, we suppose that the substance put aside was taken away and a new substance substituted for it. Accordingly, the Magen Avraham emphasizes that the owner cannot cease his search until he finds nine piles of chametz. This law applies even if the owner has nullified his ownership over the original nine piles of chametz.

Pesachim 10a likens this to a case when a person traveled through a valley in which one of the fields was known to possess a grave. Though he is unsure of whether he entered the field containing the grave or not, he must consider himself ritually impure (See Hilchot Sha’ar Avot,,.HaTum’ah 20:9.)
The Ra’avad’s text of the Mishneh Torah contained an additional clause: or there were nine piles of chametz and one pile of matzah: A loaf became separated from them and it is not known whether it was chametz or matzah. A mouse came and took it into a checked house.
The Kessef Mishneh rejects the inclusion of this clause because in the previous halachah, the Rambam had already stated that once a substance is separated from its original place, its identity is determined on the basis of the majority.

of chametz

The Pri Chadash (Orach Chayim 438:1) follows this decision even when the owner did not nullify his chametz. The Shulchan Aruch HaRav follows his opinion, though the Tur requires the owner to nullify his chametz or search.

Obviously the mouse which left is not the same as the mouse that entered, and it is not likely that one mouse took the chametz from the other (Pesachim 10b). Hence,

even if he has already nullified his chametz (Pri Chadash Shulchan Aruch HaRav).

Even though it is possible that the weasel took the chametz from the mouse, that probability is not strong enough to free the owner from the obligation to search (Pesachim, ibid.). This applies even if he nullifies his chametz (Pri Chadash, Shulchan Aruch HaRav).

the weasel’s

Even though one might say that unless the chametz is found in the mouse’s mouth, we cannot be sure that it is the same Nevertheless, since it is possible that the mouse dropped the chametz out of fear (Pesachim ibid.)

The Talmud left this questioned unanswered.)וקית (The Pri Chadash and the Shulchan Aruch HaRav explain that this decision applies only when the owner nullifies the ownership over his chametz. In such an instance, the question is only one of Rabbinic law (for according to Torah law, the nullification is sufficient). Hence, the Rambam chooses the more lenient opinion.

This question is also left unanswered by the Talmud (Pesachim, ibid.). Therefore, the Rambam again chooses the more lenient view. In this case as well, the owner must nullify his ownership over the chametz. Thus, since the question is only one of Rabbinic law, he is not required to spend extra money when the possibility exists that the snake ate the forbidden food or took it out of his premises.

even if he must rent the ladder

And the owner might come to eat it.

to which a person does not have easy access

The Maggid Mishneh emphasizes that a person is not allowed to store chametz in a pit. However, should chametz accidentally fall into the pit bef ore it becomes forbidden...

However, if he had not nullified ownership over his chametz and did not discover the chametz until after it becomes forbidden, he is obligated to remove the chametz from the pit (Mishnah Berurah).
The Tosefta (Pesachim 3:3) states: “Chametz which fell into a pit is considered as if it has been destroyed;” implying that even nullification is unnecessary. However, the Tzafnat Paneach differentiates between the two cases, explaining that our halachah ref ers to a pit to which a person could descend if required. In contrast, the Tosefta refers to a pit which is totally inaccessible, or accessible only with extreme difficulty. Since the owner cannot make use of his chametz, there is no necessity for him to nullify his ownership of it.

Generally, all prohibitions against eating forbidden foods do not apply after the food is no longer fit for human consumption. Nevertheless, additional stringencies are placed on chametz, because it may be useful as a leavening agent even if it is no longer fit to be eaten by a human being. Hence, it is not nullified until it is no longer fit even for animal consumption. (See Ra’avad, Maggid Mishneh, and Kessef Mishneh to Chapter 1, Halachah 2.)

The Mishnah Berurah (Orach Chayim 442:42) explains that if the surface of the block is covered with mortar, it does not become forbidden even though it is still fit to be eaten. This act clearly implies that the owner no longer considered the chametz as food.

Its possession does not violate the prohibition against owning chametz.
The Taz emphasizes that only the prohibition against owning chametz is lifted. Even if the chametz is unfit for animal consumption, a person is forbidden to eat it on Pesach should he desire to do so.

As mentioned in Halachah 1:1, the size of an olive is considered the minimum amount for which one is liable for the transgression of most of the Torah’s prohibitions.

The Shulchan Aruch HaRav emphasizes that this applies even when one has nullified his ownership over this chametz or covered it with mortar. The size of an olive is considered as a significant amount and must be destroyed at all times:

of dough in one place, though there are many smaller pieces of dough throughout the kneading trough

the dough

and thus, part of the kneading trough

and, theref ore, need not be destroyed.

If the dough does not serve a useful purpose

for the obligation to search after and destroy chametz applies to all quantities of that substance, even if they are smaller than the size of an olive (Maggid Mishneh).
The Shulchan Aruch HaRav (Orach Chayim 442:28) explains that dough which has not become stuck to the cracks of the kneading trough must be removed. However, leniency may be taken regarding dough stuck in the cracks of the kneading trough, even though it does not serve a purpose. Should the owner nullify his ownership over his chametz, that dough need not be destroyed if:
a) the entire kneading trough contains less than an olive size of chametz stuck to its sides;
b) the dough has become dirty and unfit for consumption.

used to fill cracks in the kneading trough

Thus, the question is raised:
Are the two considered as a single quantity, and hence obligated to be destroyed;
or
Can they be considered as separate entities, and thus allowed to be kept?

This leniency applies only to dough that strengthens the kneading trough. Otherwise, they must be destroyed (Mishnah Berurah, Orach Chayim 442:35).

leniency

whether the dough is used to fill cracks in the house or not

Based on this decision, whenever there is more than the size of an olive of dough in the same room, we are obligated to destroy any and all pieces of dough in the room, even if they are not connected by strings of dough.

when the house is swept, and thus produce a quantity the size of an olive (Rashi, Pesachim 45b).

where it would be unlikely for the two halves to come together (ibid.);

where there is a greater probability of the two small portions of chametz coming together

Generally, the word תיב means “house.” However, it is often used to mean “room.”

where the probability is even greater.

This is a major point of debate among the halachic authorities. Rabbenu Asher (Pesakim, Pesachim 3:2) writes that the dough need not be stuck to the walls of the house. However, the Maggid Mishneh and the Kessef Mishneh oppose that thesis. They argue that the only reason for leniency is that when the dough is stuck to the walls of the house, it is considered as part of the house and not as an entity in its own right.

After describing the above laws in detail, the Shulchan Aruch HaRav (Orach Chayim 442:30) concludes:
The above represents the law itself. However, the Jews are holy and have customarily accepted greater stringencies upon themselves. They scrape away even the slightest amount of chametz, even if it is stuck to the walls of a home or utensil. They have accepted the stringency of scraping down all benches, chairs, and walls that have come into contact with chametz.

One might suppose that the sequence of this halachah and the following halachah should be reversed. First, the Rambam should state who is obligated to search for chametz, and only then the fact that we can rely that this search was properly carried out. Indeed, Pesachim 4 and the Shulchan Aruch follows that sequence when discussing these laws.
Possibly, the Rambam’s choice of sequence can be explained as follows: The motivating principle of many of the previous halachot is that once a person has nullified the ownership over his chametz, the search is merely a Rabbinic obligation. Hence, many leniencies can be taken.

Pesachim 4b questions whether we can rely on this presumption or not and does not arrive at a conclusion. Nevertheless, the Rambam’s statements can be understood in light of the Pesakim of Rabbenu Asher. He explains that if ownership over the chametz is negated the obligation to search is only Rabbinic. When doubt arises regarding matters of Rabbinic law, the more lenient position may be accepted.

The Shulchan Aruch (Orach Chayim 437:2) qualifies this statement, requiring the prospective tenant to ask the owner of the house if it has been searched. However, if he cannot possibly ask the owner, he need not search the house. However, this applies only when the tenant has the opportunity to nullify his ownership over any chametz that may be found within the home.

and we know that before Pesach, chametz had definitely been kept within the home (Mishnah Berurah)

The Shulchan Aruch HaRav and the Mishnah Berurah emphasize that this law applies only if the chametz has been nullified. Otherwise, the statement of a. woman or child may not be relied upon.
Generally, a woman’s statements are accepted even as regards Torah prohibitions. However, an exception is made in this case because the search for chametz involves much effort. Hence, our Sages worried that perhaps a woman might state that she had made a thorough search even though she had merely made a superficial inspection (Tosefot, Pesachim 4b)

Tosefot (ibid.) states that slaves are believed in matters where a woman’s word is accepted.

Eruvin 58b and Ketubot 28a quote instances where a child’s statements are not accepted even with regard to Rabbinic prohibitions. However, we may rely on their word regarding the search f or chametz, because they are capable of perf orming the search.

I.e., he has reached the age where his parents have begun to educate him about the prohibition against possessing chametz.

Different rules apply to a sale (Rabbenu Nissim).

the beginning of the

I.e., the night between the thirteenth and the fourteenth.

Rashi (Pesachim 4a) explains that giving the keys to the tenant represents the transfer of ownership of the house to the tenant. Whoever is the rightful owner of the property at the time the obligation to search begins must carry out this mitzvah. However, Tosafot and most other halachic authorities explain that giving the keys does not formalize the act of transfer. Thus, the Maggid Mishneh explains that in this instance, the rental agreement has been concluded beforehand. Nevertheless, since the landlord is still in possession of the keys, the tenant is not able to conduct the search. Hence, the responsibility becomes that of the landlord.

He is required to undertake this search, even though he has abandoned ownership over any chametz that might be left in the house and does not violate the prohibitions against possessing chametz because of it (Shulchan Aruch HaRav 437:1).

However, the Mishnah Berurah mentions other opinions that require a search even if the tenant has not formalized the rental agreement.

Even though the chametz was left by the landlord, when the tenant takes over the ownership of the house, he becomes the owner of all its contents, including the chametz.

If the landlord is available, the tenant must ask him whether the house has been searched or not.

He must carry out the mitzvah even though he made an explicit condition requiring the landlord to do so.

Under certain conditions, a person can nullify a business agreement on the grounds that it was carried out under false premises.

in that locale

Pesachim 4b explains that the need for searching the house is not the real factor motivating him to retract his agreement, because every Jew desires to perform mitzvot, even if doing so requires financial expense.
Based on the Maggid Mishneh, the Ramah (Orach Chayim 437:3) requires the landlord to reimburse the tenant if it is customary to hire people to search. After all, the house was rented with the explicit condition that it had been searched.

Furthermore, any chametz which he knows about must be removed from his possession (Magen Avraham, Orach Chayim 436:1.

At night by candlelight before he departs (Magen Avraham). However, no blessing is recited (Shulchan Aruch). The Shulchan Aruch emphasizes that this law applies only when a person does not leave anyone else at home (e.g., a wife or older child) who could conduct the search at the customary time.

Thirty days before Pesach, we begin “asking and explaining the laws of the holiday.” Hence, from that time onward, concern is shown for all the Pesach laws (Pesachim 6a).

Even if his intention is to return far bef ore Pesach, if there is a likelihood that his return may be delayed until the holiday, he must search before departing (Chatam Sofer).

Even if he departs at the beginning of the year (Pesachim 6a).

The Shulchan Aruch HaRav 436:9 and the Mishnah Berurah 436:9 maintain that this law applies only when the person is going on a sea voyage or caravan where delay is a frequent phenomenon. A person who sets out on a sure land journey is not obligated to search before he departs.

As stated in Halachah 1:9, the prohibitions against possessing chametz begin after the conclusion of the fifth hour on the fourteenth of Nisan. From that time onward, it is forbidden to nullify any chametz that we possess.

until after Pesach

Nevertheless, he is obligated to nullify any chametz that might be in his possession on Pesach eve. This nullification takes effect even though he is very far from the chametz in his home (Ramah; Magen Avraham).

chametz which is buried under more than three handbreadths ofother substances is considered as having been removed from a person’s property and need not be uncovered and destroyed before Pesach. (See Halachah 3:11.) Thus, making the house a storeroom and covering any chametz with more than that amount ofother material would free him from the obligation of searching (Rashi, Pesachim 6a).
However, the Sages explain that this leniency applies only to chametz which accidentally becomes covered by other substances.

intentionally covering the chametz with other goods

Once the thirty-day period when the Pesach laws begin to be studied arrives, one is obligated to search.

The Kessef Mishneh (and the Shulchan Aruch) quote certain opinions that do not obligate a. search, explaining that it is far less likely that the person will be delayed in removing his goods and bring about a situation where he will uncover the chametz on Passover eve.

The Mishnah Berurah (437:15) explains that most authorities allow this leniency only when the owner has only a suspicion, but no definite knowledge of chametz. However, if he definitely knows that chametz is found under the goods, the chametz must be removed. Nevertheless, there are some opinions that do not require the removal of chametz whose existence is known.