conduct is self-evident and requires no explanation or inquiry. Yet he said:

“Do not betray the one who betrays you.”

It is therefore clear that he meant that you must not respond to someone’s betrayal by doing to him what he did to you. If a man is entrusted with money and betrays its owner with respect to part of it, and the owner is subsequently entrusted with an equivalent amount and treats him in the same way, this is what is meant by his words:

“Do not betray the one who betrays you.”

Third, there is no doubt that this constitutes betrayal. The question is only whether it is permissible by way of retaliation. For some acts, retaliation is permissible, as in cases of killing, highway robbery, and the taking of property. For others, retaliation is not permissible, such as acts of indecency, lying, and the like. Concerning the former, Allah Most High says:

“The recompense of an evil deed is an evil like it.”

He also says:

“If you retaliate, then retaliate with the like of what you were made to suffer.”

And He says:

“Whoever transgresses against you, transgress against him in the same measure as he transgressed against you.”

Thus, He permitted punishment and retaliation in equal measure. But when he said here, “Do not betray the one who betrays you,” it became clear that this belongs to those acts for which punishment in kind is not permissible.

He—may Allah have mercy on him—was asked about a man who owed a debt and had merchandise in his creditor’s possession. The price owed was seventy dirhams, while the merchandise was worth ninety dirhams. The debtor had died, and his assets had been secured. The creditor wished to inform the heirs of the merchandise