The Prophet ﷺ said, "Usury has seventy-three categories."
حدثنا عمرو بن علي الصيرفي أبو حفص حدثنا ابن أبي عدي عن شعبة عن زبيد عن إبراهيم عن مسروق
عن النبي ﷺ قال الربا ثلاثة وسبعون بابا
No references are available.
[Hasan] Reported by Hakim: 2/37, from the hadith of Amr bin Ali with this wording, "riba has seventy-three doors, the least serious of which is like a man marrying his mother, and the worst form of riba is a Muslim man violating another Muslim's honor." He declared it sahih according to the standard of the two Shaykhs, and Dhahabi agreed with him. Busiri said, "This isnad is sahih."