2,778. Lending to and Borrowing From Shimon

Continuing the case of Reuvein, who is prohibited to benefit from Shimon.

Hilchos Nedarim 6:15

If Reuvein was only prohibited by a vow or an oath to benefit from Shimon’s food and the prohibition took effect before the Sabbatical started, then he would be permitted to enter Shimon’s field but not to eat his produce. If the prohibition took effect during the Sabbatical, then he would be permitted both to enter the field and to eat the produce because the produce no longer belongs to Shimon. Rather, it has been rendered ownerless.

Hilchos Nedarim 6:16

Reuvein is not permitted to lend things to Shimon. This is a preventive measure out of concern that Reuvein might come to borrow from him, which is prohibited as a form of benefit. Similarly, Reuvein may not lend Shimon money out of concern that he might come to borrow from him. He may likewise not sell something to Shimon lest he come to buy from him.