Mukhtasar Bukhari (Abridged) 992 — Prophet's practice of buying

Narrated from Sayyiduna Anas (may Allah be pleased with him) that he took “barley bread” and “fat” to the Prophet Muhammad (peace be upon him), and (at that time) the Prophet Muhammad (peace be upon him) had mortgaged his armor in Madinah with a Jew and had bought some barley for his family with it. (Sayyiduna Anas, may Allah be pleased with him) says: Indeed, I heard the Prophet (peace be upon him) say: “The family of Muhammad does not have even a sa’ (measure) of wheat or any other grain left for the evening, even though he had nine wives.”