(The Mishnah stated in 10-2(c)): Whatever he leaves over after checking should be hidden away to avoid the need to check again.

Question: What should he do?

Answer: He should overturn a vessel on top of it.

If he overturned a vessel and then later found that it was missing, one can assume that it was removed (and there is no need to check again).

Query: If he did not overturn a vessel on top of it and then found it missing, must he check only that house (again) or all the other houses as well?

Answer: One could answer it from the Beraisa -

If one lost a kzayis (olive-sized piece) of a corpse in a house and then searched but could not find it, the house is Tahor.

If it was later found, the house is retroactively Tamei.

These two beraisos (Pesach and Tum'ah) can teach one another -

The case of Pesach teaches that even if one had set down the object (rather than lost it) and then found it to be missing, one is still required to search for it.

The case of Tum'ah teaches that one is only required to check that house but no other.

Question: One can learn from the following Beraisa that Rebbi Yehudah holds that even that house would not require checking! - There was a story with the handmaiden of an olive-picker in Rimon who threw her miscarried foetus into a pit and a Kohen came and gazed into the pit in order to discern what she had thrown there (male or female - as the mother needed to know this for her purification process). The case came before the Chachamim and they determined that the Kohen was Tahor, since it is the way of weasels and martens to drag away meat from there. (This shows that if one left Chametz uncovered and then found it to be missing, one need not check again since one could assume that it was taken away by a small animal?)

Answer #1: Such an animal would pursue meat but not bread. (Rather it was likely moved by a child or trodden into the ground.)

Answer #2: One can say that it would also pursue bread; however, it would drag away meat and eat it but it would drag away bread and leave it (and therefore the house still requires checking).

(Rabbis of Caesarea): One need not be concerned that it was dragged away by a weasel. However, according to Rebbi Yehudah one must be concerned [that the Chametz was dragged away](If Rebbi Yehudah uses the possibility of the weasel dragging away as a leniency (in the case of Tum'ah), then certainly he would say it as a stringency in the case of Chametz. Therefore, the house must be checked).

(Mishnah - Rebbi Meir): One may eat during the entire 5th [hour](of the day of the 14th of Nisan) and one burns at the beginning of the 6th [hour].

(Rebbi Yehuda): One may eat during the entire 4th, one is Toleh during the 5th (he may not eat it but he is not yet required to burn it - he may feed it to his animals) and one burns at the beginning of the 6th.

(Gemara): Rebbi Meir holds that the prohibition to eat Chametz after the 6th hour is Rabbinic. Rebbi Yehudah holds that it is Scriptural.

Question: What is Rebbi Meir's source?

Answer (Shemos 12, 15): "...but (ach) on the first day [you must destroy leaven from your houses]'', refers to the 15th [of Nisan]. One might think that this refers to after nightfall...? The pasuk says "ach''. How is this? One must include one hour before sunset into this law (in the afternoon of the 14th).

Question: What is Rebbi Yehuda's source?

Answer: "...but (ach) on the first (previous) day'', refers to the 14th. One might think that this refers to the entire day...? The pasuk says "ach''. How is this? Divide the day, with half for Chametz and half for matzah.