Two neighbors in a building, a grandfather and his grandson, presented to us the following inquiry. After 10 years of living there and paying their utility bills they realized that the gas company had been sending the grandson the bill for his grandfather’s gas usage, and vice versa. The grandson made a calculation and it turns out that he paid thousands of dollars more than he was obligated to pay. The grandfather claimed he did not owe the grandson the difference.

Q: Is the grandfather obligated to repay his grandson for paying his gas bill all these years?

A: At first glance it seems that the grandfather’s claim is well founded. Generally, if Reuven voluntarily pays Shimon’s debt, Shimon is not obligated to reimburse him (C.M. 128:1; Shach 5). A number of reasons are given to explain this halachah.

One explanation is that it is assumed that Reuven intended to perform a mitzvah by paying Shimon’s debt and it was meant to be a gift. Sometime later Reuven regretted giving this gift, but that regret does not obligate Shimon to now reimburse him (Rashi, B.K. 58a; Shach 128:8).

Another explanation is that Shimon could claim that he would have negotiated with his creditor to forgive the debt had he known. Even if the creditor is a difficult person, it is possible for Shimon to find a relative of his to plead or pay on his behalf. Accordingly, Shimon did not benefit from Reuven paying his debt and thus he is not obligated to reimburse him (C. M. 128:1).

A third explanation is that since Shimon did not receive anything tangible from Reuven, nor did his property increase in value, Reuven did nothing more than prevent Shimon from a loss (mavri’ach ari minichsei chaveiro) but that does not obligate Shimon to reimburse him (Tosafos, B.K. 58a d.h. “i-nami”; see also C.M. 128:2 regarding Shimon’s exemption from having to reimburse Reuven, who was forced to pay Shimon’s debt ).

When we consider the above, the following emerges. According to the first reason, the grandfather must reimburse his grandson since it is clear that the grandson did not intend to perform a mitzvah by paying his grandfather’s bill but paid by mistake. According to the second reason, although it is difficult for the grandfather to claim that he would have negotiated with the gas company to forgive his bill altogether, nonetheless, he may have found others who would have covered his bill, and this reason applies even though the grandson paid the bill in error. It would seem that the third explanation would also exempt the grandfather since he did not receive material benefit from the fact that his grandson paid his bill.

It must be emphasized that, although the grandfather could claim that he is exempt due to the two explanations that support his position (kim li), nevertheless, it is definitely ethical for him to reimburse the grandson. Moreover, beis din would certainly make a compromise between them and have the grandfather repay his grandson for at least some of the amount that he overpaid.

Next week, iy”H, we will explore reasons why the grandfather is halachically obligated to reimburse his grandson fully.

For Part II click here