Musannaf Ibn Abi Shaybah 23762 — Paying in advance (salam) for food

Muhammad bin Abi al-Mujalid said: Abu Burdah and Abdullah bin Shaddad differed about the salam sale, and they sent me to Sayyiduna Ibn Abi Awfa (may Allah be pleased with him). I asked him and he said: We used to make salam sales in wheat, barley and raisins in the time of the Prophet (peace and blessings be upon him) and of Sayyiduna Abu Bakr (may Allah be pleased with him), and we do not know whether his associates had any of it with them or not.