And this day shall be to you for a memorial, and you shall keep it as a feast to the Lord; throughout your generations you shall keep it as a feast by an ordinance forever. Seven days shall you eat matzot, yet on the first day you shall remove leaven from your houses; for whoever eats leavened bread from the first day until the seventh day, that soul shall be cut off from Israel. And on the first day there shall be a sacred convocation, and on the seventh day there shall be a sacred convocation to you; no kind of labor shall be done on them, save that which every man must eat, that only may be done for you.
Matzot shall be eaten seven days; and no leavened bread shall be seen with you, neither shall there be leaven seen with you, in all your borders.
Your lamb shall be without blemish, a male of the first year; you shall take it from the sheep, or from the goats. And you shall keep it until the fourteenth day of the same month, and the whole assembly of the congregation of Israel shall slaughter it in the afternoon…And they shall eat the meat on that night, roast with fire, and matzot; with bitter herbs they shall eat it. Eat it not raw, nor boiled in water; but roast it with fire, its head with its legs and with its inner parts.
–Shemot 12:5-6, 8-9
Observe the month of aviv, and keep the Passover to the Lord your God; for in the month of aviv the Lord your God brought you out of Egypt by night. You shall therefore sacrifice the Paschal offering to the Lord your God, of the flock and the herd, in the place that the Lord shall choose to rest His name there. You shall eat no leavened bread with it; seven days shall you eat matzot with it, the bread of affliction; for you came out of the land of Egypt in haste, that you may remember the day when you came out of the land of Egypt all the days of your life.
Speak to the people of Israel, saying: If any man of you or of your posterity shall be unclean due to a dead body, or is on a journey far away, he shall still keep the Passover to the Lord. The fourteenth day of the second month at evening they shall keep it, and eat it with matzot and bitter herbs. They shall leave none of it to the morning, not break any bone of it; according to all the ordinances of the Passover they shall keep it. But the man who is clean, and is not on a journey, and refrains from keeping the Passover, that same soul shall be cut off from among his people; because he brought not the offering of the Lord in its appointed season, that man shall bear his sin.
The Torah actually describes two distinct Festivals collectively referred to as Passover, although they are often thought of as a single holiday. First is the festival of Pesah, referring specifically to the Festival surrounding the Paschal lamb, which is offered on the afternoon of the fourteenth day of Nisan and consumed later that night. This parallels the events immediately preceding the exodus from Egypt. Distinct from this is the festival of Matzot, the weeklong Festival beginning on the fifteenth of Nisan and characterized by the prohibitions against consuming or possessing leaven throughout the week, and the obligation to eat matza on the first night. This commemorates the actual exodus. There is a confluence of these two Festivals on the evening of the fifteenth, when the Paschal lamb is eaten and the festival of Passover begins.
Tractate Pesahim, which deals with both Festivals, is classically divided into two sections. The first, tractate Pesah Rishon, discusses the laws of the festival of Matzot, including the prohibition of leaven, its elimination from one’s possession, and the mitzva to consume matza. The second, tractate Pesah Sheni, deals with the festival of Pesah and the laws of the Paschal lamb. Some suggest that it is for this reason that the tractate as a whole is entitled Pesahim, the plural of Pesah, since it includes within it these two tractates of Pesah.
The tractate also deals with two Pesahim in a different sense. Ideally, the Paschal lamb is to be offered on the fourteenth of Nisan and consumed later that night. However, those who are unable to do so have a second opportunity a month later, on the fourteenth of Iyyar and later that night. The first opportunity is called Pesah Rishon, the first Passover, and the next, Pesah Sheni, the second Passover.
As stated, the festival of Matzot is characterized by the prohibition against eating or possessing leaven. Remarkably, the reason for this prohibition is neither explained by the Torah nor discussed in the Gemara. It is instructive, however, that a similar prohibition of leaven also applies to the sacrificial rite; namely, that no leaven may be offered on the altar. Instead, all grain-based offerings are unleavened. This may indicate that the exclusive consumption of unleavened produce achieves elements of purity and sanctity.
The Torah states the prohibitions concerning leaven only in general terms but never defines precisely what is intended: Which types of food can become leavened, what is the precise definition of being leavened, and does the prohibition apply to items that will not be eaten? Similarly, the prohibition against possessing leaven necessitates that it be removed from one’s home. However, the many practical implications of this are not explained by the Torah. When and how should the leaven be removed from one’s possession? Obviously, throughout the year leaven is constantly found in the home. Which areas of the home need to be checked? In what manner and to what extent? The prohibition against leaven includes both eating it and deriving benefit from it. What is included in this prohibition? This question itself raises more general issues regarding other prohibited foods and items from which one is not allowed to gain benefit. All these topics are discussed in the first section of the tractate, Pesah Rishon.
The second section of the tractate, Pesah Sheni, provides a detailed discussion of all aspects of the rite of the Paschal lamb and the Temple service surrounding it. This section closely resembles tractates within the order of Kodashim, which deals with the sacrificial rite. The style of the Gemara’s analysis of the sacrificial rite differs significantly from that employed by the Gemara in other areas. Heavy emphasis is placed on hermeneutics, and references to halakhot given to Moses at Sinai are more prominent. Principles derived in one area of the Temple service are not always immediately applied to another, as each aspect of the service maintains an independent identity.
Owing to the great sanctity of the offerings, there is a plethora of rules that apply to every stage of their rites. Significantly, and unlike most other mitzvot, emphasis is placed not only on the correct physical performance of the rite but also on the intentions of those involved. Improper intent can even, at times, entirely disqualify an offering.
The Paschal lamb is, in one regard, just one of the many different offerings sacrificed in the Temple. As such, all the halakhot that apply to regular offerings apply to a Paschal lamb. For example, the sacrifice of all offerings comprises four sacrificial rites, all indispensable: The animal is slaughtered, its blood is collected in a holy vessel, it is carried to the altar, and then the blood is sprinkled upon the altar. Each of these rites must be performed correctly, and failure to do so can disqualify the offering. In addition, the many types of offerings are grouped into different subcategories, each with its own halakhot. The Paschal lamb is included within various subcategories, which provide a second level of halakhot that must be followed.
However, there are many halakhot that are unique to the Paschal lamb. For most offerings, the consumption of its meat, whether by the priests or by those bringing the offering, is of minor importance. Even if an offering might never be consumed, it may still be permissible to bring it. Not so for the Paschal lamb. The consumption of its meat by those bringing it is one of its central purposes, and a Paschal lamb that will not be eaten may not be brought at all. There are therefore numerous laws pertaining to its preparation and consumption. This includes the way it is roasted, the need for those who wish to partake of it to be registered into a group beforehand, and the manner in which it is eaten.
The Paschal lambs that were offered by the children of Israel in Egypt provide a paradigm for the Paschal lambs that are to be offered each year throughout the generations. Accordingly, many of the laws of the Paschal lamb parallel those that were given to the children of Israel in Egypt. In this way the Paschal lamb is able to serve as a remembrance of the exodus from Egypt throughout the generations.
The tractate is structured chronologically, beginning with the required preparations before the Festival begins, including the elimination of leaven from one’s possession. It then proceeds to discuss the offering of the Paschal lamb on the fourteenth of Nisan, and concludes with the details of the Seder night on the fifteenth. In the first few chapters of the tractate, incidental to the discussion of the elimination of leaven from one’s possession, it provides a more general discussion of the nature of the prohibitions pertaining to leavened bread.