The ruling on one who swears by divorce regarding the sale of goods

Question:
Two men bought and sold, then they disagreed in the assembly. The seller said, "By divorce," and he repeated it more than twice, swearing that he would never sell to the buyer who was present with him in the assembly. Then, after that, he decided to sell. What is the ruling on that?

Answer:
First, it is not befitting to use divorce in this matter, and the least of its states is that it is disliked; because it may lead to divorce, it may lead to separation and the ruin of the home.
Then, expressing it by divorce is not permissible; because it is an oath by other than Allah, so saying "by divorce" or "by prohibition" or "by what is forbidden" is not permissible; because it is an oath by other than Allah, it is not permissible.
But if he says: "Divorce is upon him if he sells," "Divorce is upon him if he does not speak to so-and-so," there is a detail in this:
If his intention is to prevent himself from this thing, and he did not intend her divorce, his intention is not to separate from his wife, but rather his intention is to emphasize to himself that he will not sell to him, this is his intention: he will not sell to him; upon him is the expiation of an oath if he sells to him.
As for if his intention is to effect the divorce: he sold now on the condition that the divorce falls upon his wife, then if he sells, the divorce falls, so he should not sell if he loves that his wife remains with him and that the divorce does not fall.
As for if he did not intend anything but mere emphasis and preventing himself from selling, his intention is not to effect the divorce, and his intention is not to separate from his wife, but he wanted by this to emphasize that he will not sell; then in this is the expiation of the oath if he sells.