Pesachim 1,5

MISHNA: R. Meir says: "It is lawful to eat (Chometz on the 14th of Nissan) the whole of the first five hours and what remains must be burned at the commencement of the sixth hour," but R. Jehudah says: "It is only permitted to eat (Chometz) the first four hours; during the whole of the fifth hour this must be abstained from and it must be burned at the commencement of the sixth hour."

R. Jehudah also taught: Formerly (during the existence of the Temple) two cakes of thanksgiving- offering which had become desecrated were exposed on a bench (of the Temple). As long as the two cakes remained there, all the people still ate leavened bread; when one of them was removed, they abstained from eating it but did not yet burn it; when both were removed, all the people commenced burning (the Chometz). Rabbon Gamaliel says: Ordinary (Chometz) may be eaten during the first four hours; but heave-offering may still be eaten during the fifth hour; both, however, must be burned at the commencement of the sixth hour.

GEMARA: We see thus, that at the commencement of the sixth hour, all agree, Chometz must be burned. 1 Whence do we adduce this? Said Abayi: From two passages, viz. [Exod. xii. 19]: "Seven days no leaven shall be found in your houses," and [ibid. 15]: "But on the first day ye shall have put away leaven out of your houses." According to this, then, on the first day there would still be leaven in the house and this would be contrary to the ordinance of the first passage? Hence we must say, that by "the first day" is meant the day preceding the festival. Then why say the sixth hour? Say that already early in the morning of the day preceding the festival (leaven should be burned). The word "but" with which the passage commences divides the day into two parts, so that in the morning leavened bread may be eaten while in the afternoon it must not.

The disciples of R. Ishmael taught: The reason that Chometz must be removed on the 14th (of Nissan) (the eve of Passover) is because that day is referred to as the first day (of the festival) in the passage [Exod. xii. 18]: "In the first, on the fourteenth day of the month, at evening shall ye eat unleavened bread," etc.

Rabha said: "The reason may be inferred from the passage [Exod. xxxiv. 25]: 'Thou shalt not offer the blood of my sacrifice with leaven; neither shall be left unto the morning the sacrifice of the feast of the passover,' which signifies, that the Passover sacrifice must not be offered up as long as there is yet leaven." If that be the case, then it might be said that the leaven should be burned by each man immediately before offering his passover sacrifice; why designate the sixth hour? The passage means to state, that when the time for the Passover sacrifice arrives, there must no longer be any leaven on hand.

The disciples of R. Ishmael taught: The reason that Chometz must be removed on the 14th (of Nissan) (the eve of Passover) is because that day is referred to as the first day (of the festival) in the passage [Exod. xii. 18]: "In the first, on the fourteenth day of the month, at evening shall ye eat unleavened bread," etc.