What did the Prophet Muhammad (saw) mortgage as payment towards a purchase of foodstuff he made from a Jew on credit?
 Narrated Al-A`mash:                     We argued at Ibrahim's dwelling place about mortgaging in Salam. He said, "Aisha said, 'The Prophet bought some foodstuff from a Jew on credit and the payment was to be made by a definite period, and he mortgaged his iron armor to him."