Muhammad bin Isma'il bin Ibrahim محمد بن إسماعيل بن إبراهيم بن مقسم · The Chapters on Business Transactions

"The last thing to be revealed was the Verse on usury but the Messenger of Allah (ﷺ) died before he had explained it to us. So give up usury (interest) and doubtful things."

"The Messenger of Allah (ﷺ) used to accept the invitation of a slave."