MISHNAH: If somebody is forbidden any profit from another person by a vow, he should not borrow from him nor ask him for anything1, should not give him a loan nor take a loan for him, should not sell to him nor buy from him. If he said, lend me your cow, he says: she is not available. If he said, a qônam that I shall never plough with her, if he usually ploughs, he is forbidden, the rest of the world is permitted2. If he does not usually plough, he and the rest of the world are forbidden.
1. Tools or animals.
2. His agricultural workers may still use that cow to plough his field.