Sale of Chametz

We are required to get rid of our chametz before Pesach, and of course one way of doing this is to sell it to someone else - especially making an earnest sale to a non-Jew, who will be able to benefit from the chametz during Pesach. However, apart from this way of getting rid of one’s chametz for good, it has been a custom for thousands of years to allow a sale to a non-Jew in which it is understood that the plan is to buy the chametz back from the buyer after Pesach, after giving him a token profit on the deal (Tosefta Pesachim 2:12-13).

This is actually a very significant leniency. In some areas of halakha, reversible sales are not considered a valid way of circumventing prohibitions (see e.g. SA YD 174 1-3). Furthermore, sometimes these sales are not done in a way which is completely satisfactory from a strict legal perspective. Why is such a sale sufficient here?

The Rabbis:Rav Nissim Gerondi (Ran)Ra"N asked the same question regarding nullification of chametz. Where else in halakha do we find that we can evade responsibility for something merely by affirming to ourselves that we don’t esteem it? His answer is that on Pesach the chametz is not completely ours anyway - after all, we may not obtain any benefit from it! Since our level of ownership is weak, so also the requirements for evading ownership are weak. (Ra"N on the Ri"F, beginning of Pesachim, d.h. umahu.) This same idea can be extended to the idea of a sale which doesn’t meet the same standards required in other areas of halakha. (MB 448:17.)

Yet there seems to be an additional problem even if the sale is completely valid. Even though nullification of the chametz is really sufficient to avoid the problem of possessing chametz on Pesach, our Sages required eliminating chametz from the house completely; one reason is that if there is chametz in the house there is a chance that we may come to eat it. (MB 431:2.)

Why aren’t we afraid that we will be tempted to eat the chametz of the non-Jew? After all, he will never know the difference, since the chametz is invariably bought back right after Pesach. And while it is true that we must make a low partition to remind ourselves not to eat this chametz (SA CM 440:2), such a partition is not enough for our own chametz, which must be ruthlessly eliminated even if it is in an out-of-the-way place.

It seems that in this case our Sages relied on our inner instincts of ethical behavior.

Once we have sold the chametz to the non-Jew, eating it would be stealing. Of course the non-Jew would never know about this theft, and even if he knew it would make no difference to him. Even so, Chazal relied on us not to touch a bit of chametz which does not belong to us. While our temptation to eat could overcome the severe religious prohibition of eating chametz on Pesach, they were certain that it would never overcome the ethical prohibition of stealing.