The time for the removal of leaven is juxtaposed to the time when the eating of leavened bread is prohibited. When the prohibition against eating leaven goes into effect, the obligation to remove leaven is in effect as well. And furthermore, the time of the prohibition against the eating of leavened bread is juxtaposed to the time for the eating of matza, as its prohibition takes effect from the time that the mitzva to eat matza takes effect.

The Gemara elaborates: The removal of leaven is juxtaposed to the eating of leavened bread, as they appear in the same verse, as it is written: “Seven days leaven shall not be found in your houses, as anyone who eats that which is leavened, that soul shall be cut off from the congregation of Israel” (Exodus 12:19).

And the prohibition against the eating of leavened bread is juxtaposed to the eating of matza, as both appear in the same verse, as it is written: “You shall not eat anything that is leavened; in all of your dwellings you shall eat matzot, etc.” (Exodus 12:20), and it is written with regard to matza: “On the first day, on the fourteenth day in the evening you shall eat matzot” (Exodus 12:18). Since the halakha that leaven is prohibited on the first night of Passover is derived from this source, there is no need for an additional derivation.

The Gemara asks: And say that the verse: “Yet on the first day you shall remove leaven from your houses” comes to include the night of the fourteenth in the obligation to remove leaven, which would mean that one must remove all leaven from his house on the night of the fourteenth. The Gemara rejects this suggestion: That is not possible, as “on the day” is written.

The Gemara continues to ask: And say that leaven must be removed immediately from the morning of the fourteenth. The Gemara answers: That is also incorrect, as the verse says, “Yet on the first day”; and the word yet divides. The connotation of the word yet is one of restriction. In this context, it teaches that leaven is prohibited not for the entire day, but only for part of it. One is obligated to remove leaven only for the second half of the fourteenth of Nisan, not for the first half of the day.

The school of Rabbi Yishmael taught: We found that the fourteenth day is called: First, as it is stated: “On harishon, on the fourteenth day of the month” (Exodus 12:18). Rav Naḥman bar Yitzḥak said: It is evident from the verse itself that it is referring to the removal of leaven on the fourteenth, as rishon means previous. In this context, first means the day that precedes the others, i.e., the day before the Festival begins, as the verse stated: “Are you first [rishon] man born? Or were you brought forth before the hills?” (Job 15:7). Based on the parallelism between the two parts of the verse, the word rishon here means before; the one preceding all others.

The Gemara asks: But if that is so, consider a verse written with regard to Sukkot: “And you shall take for yourselves on the first [harishon] day the fruit of a beautiful tree, branches of palm trees, and boughs of thick trees, and willows of the brook” (Leviticus 23:40). So too, in this case, does harishon mean the day previous to the Festival? Clearly, one is not obligated to take the four species on the fourteenth of Tishrei, the eve of Sukkot.

The Gemara rejects this contention. There it is different, as it is written immediately thereafter: “And you shall rejoice before the Lord your God seven days” (Leviticus 23:40). Just as the seventh of these seven days is the seventh day of the Festival, so too, the first of these days is the first day of the Festival itself, not the day before Sukkot. However, where it is not explicitly stated, rishon means the day before the Festival.

The Gemara raises a difficulty. Here too, it is written with regard to Passover: “Yet on the first [harishon] day you shall remove leaven from your houses”; “for seven days you shall eat matza” (Exodus 12:15). Just as seventh here is referring to the seventh day of the Festival, so too, rishon must refer to the first day of the Festival. The Gemara answers: If so, let the verse write rishon; why do I need the addition of the definite article, harishon? Learn from it, as we said: Harishon means the day before the Festival.

The Gemara raises an objection: If so, there too, with regard to Sukkot, why do I need the verse to say harishon? And furthermore, there it is written: “On the first [harishon] day a solemn rest and on the eighth day a solemn rest” (Leviticus 23:39). Here too, say that first means previous, the day preceding the Festival. The Gemara rejects this suggestion: It is different there, as the verse said: “And on the eighth day a solemn rest,” from which it can be inferred that just as the eighth means the eighth day of the Festival, so too, rishon is referring to the first day of the Festival.

The Gemara repeats its earlier question: Why do I need the verse to say harishon? The Gemara answers: The definite article comes to exclude the intermediate days of the Festival. It is not prohibited to perform labor on these days, as the full-fledged sanctity of the Festival does not apply to them. The Gemara says: The status of the intermediate days is derived from the words first and eighth. The fact that the verse mentions only the first and the eighth days as Festivals clearly indicates that the days between them are not Festivals.

The Gemara answers: Nevertheless, a special verse was necessary to exclude the intermediate Festival days, as otherwise it could enter your mind to say that since the Merciful One writes: “And on the eighth day,” the principle: The letter vav adds to the previous matter, applies. When a phrase begins with the conjunction vav, meaning and, it is a continuation of the previous matter rather than a new topic. Based on this principle, I might have said that one must treat even the intermediate days as full-fledged Festival days. Therefore, the definite article teaches us not that this is not so.

The Gemara asks: And let the Merciful One write in the Torah neither the conjunction vav nor the definite article heh. Since they neutralize each other, as explained above, the same result could have been achieved by omitting both. And furthermore, there, in its description of Passover, it is written: “On the first [harishon] day you shall have a sacred convocation; you shall do no servile work” (Leviticus 23:7). Does first mean previous, the day preceding the Festival, in this case too? Labor is permitted on the eve of the Festival.

Rather, the Gemara explains that those three times the word rishon is mentioned with regard to the Festivals are necessary for that which the school of Rabbi Yishmael taught. As the school of Rabbi Yishmael taught: In reward for the three times the word rishon is stated with regard to the Festivals observed by the Jewish people, they were entitled to three matters also referred to as rishon: To eradicate the descendants of Esau, to the construction of the Temple, and to the name of Messiah.

The tanna provides the sources for his statement. To eradicate the descendants of Esau, as it is written: “And the first [harishon] came forth red, all over like a hairy mantle; and they called his name Esau” (Genesis 25:25). And to the construction of the Temple, as it is written: “The Throne of Glory, on High from the beginning [merishon], the place of our Temple” (Jeremiah 17:12). And the Jewish people were also entitled to the name of Messiah, as it is written: “A harbinger [rishon] to Zion I will give: Behold, behold them; and to Jerusalem a messenger of good tidings” (Isaiah 41:27). However, harishon stated with regard to Passover is referring to the day before the Festival.

Rava said: The halakha that leaven is prohibited from midday on the fourteenth of Nisan is derived from here: “You shall not slaughter the blood of My offering over leavened bread; neither shall the offering of the feast of the Passover be left to the morning” (Exodus 34:25). This verse means that you shall not slaughter the Paschal lamb while your leavened bread is still intact. In other words, all leaven must be removed before the time the Paschal lamb may be slaughtered.

The Gemara raises a difficulty: And say that the verse means that each and every person must ensure that he has no leaven in his possession when he slaughters his own Paschal lamb, and there is no fixed time for this prohibition. The Gemara answers: The Merciful One states the time of the slaughter of the Paschal lamb, which begins at the end of the sixth hour. In other words, this verse is referring to a particular point in time, rather than the individual act of slaughtering the Paschal lamb.

The Gemara adds that some of the aforementioned opinions were also taught in a baraita: “Yet on the first day you shall remove leaven from your houses” (Exodus 12:15). This prohibition is in effect from the eve of the Festival. Or perhaps that is not the case, but it applies only to the Festival itself. The verse states: “You shall not slaughter the blood of My offering over leavened bread” (Exodus 34:25), meaning that you shall not slaughter the Paschal lamb while your leavened bread is still intact. This is the statement of Rabbi Yishmael.

Rabbi Akiva says: There is no need for this proof, as it says: “Yet on the first day you shall remove leaven from your houses,” and it is written: “And on the first day there shall be to you a sacred convocation, and on the seventh day a sacred convocation; you shall perform no manner of work on them” (Exodus 12:16). And we found that kindling a fire is a primary category of prohibited labor. Since the fire in which the leaven is burned is not for the preparation of food, kindling it is not performed for the purpose of the Festival. Therefore, it is prohibited to burn the leaven on the Festival itself. Consequently, one must burn the leaven on the day before the Festival.

Rabbi Yosei says: There is no need for that proof either, as it says: “Yet on the first day you shall remove leaven from your houses.” This prohibition applies from the eve of the Festival. Or perhaps that is not the case, but it applies only to the Festival itself. The verse states: Yet, which comes to divide the day into two parts; the first half, when leaven is permitted, and the second half, when it is prohibited. And if this verse is referring to the first day of the Festival itself, is leaven permitted on the actual Festival? As explained above, the removal of leaven is juxtaposed to the eating of leavened bread, and the eating of leavened bread is juxtaposed to the eating of matza. Rava said: