We say: It was to emphasize that deferred-exchange usury is graver than excess usury, because this was the form known in the pre-Islamic era. When a person borrowed from another and the term fell due but he could not repay, the creditor would say, “We will defer it and increase it.” It is as though he said: The gravest and most sinful form of usury is deferred-exchange usury. From this we know that there can be no contradiction between one statement of the Prophet, peace and blessings be upon him, and another, if both are authentically reported from him. Rather, both must be acted upon unless abrogation is established.
If someone asks: Then what is the benefit of restricting it to this?
We say: Because it is the graver of the two types of usury. This is why he said, “Usury is only in deferred exchange.”
So, in what things is deferred-exchange usury prohibited?
His statement, “Deferred-exchange usury is prohibited”: nasī’ah means that which is deferred, as Allah, Exalted is He, says:
“Indeed, postponing [the sacred months] is an increase in disbelief, by which those who disbelieve are led astray.” [al-Tawbah 9:37]
That is, postponement. However, the verse does not refer to deferred-exchange usury. Rather, it refers to what Allah explains at the end of the verse:
“They make it lawful one year and unlawful another year.”
This is because fighting was forbidden during the sacred months—Rajab, Dhu al-Qa‘dah, Dhu al-Hijjah, and Muharram. The Arabs would manipulate them: at times, they would postpone Muharram until Safar, declaring Muharram lawful and Safar sacred. Allah says:
“So that they may conform to the number of months that Allah has made sacred”—not the particular months that Allah made sacred. For their number is four; thus, they conformed to the number, but differed regarding their designation. Hence He says, “thereby making lawful what Allah has forbidden.” Thus, the postponement mentioned in the verse differs from the deferment being discussed here. The deferment under discussion here is the delaying of