Sahih Bukhari Volume 3, Book 35, Hadith 2253

حَدَّثَنِي مُحَمَّدُ بْنُ مَحْبُوبٍ، حَدَّثَنَا عَبْدُ الْوَاحِدِ، حَدَّثَنَا الأَعْمَشُ، قَالَ تَذَاكَرْنَا عِنْدَ إِبْرَاهِيمَ الرَّهْنَ فِي السَّلَفِ فَقَالَ حَدَّثَنِي الأَسْوَدُ عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم اشْتَرَى مِنْ يَهُودِيٍّ طَعَامًا إِلَى أَجَلٍ مَعْلُومٍ، وَارْتَهَنَ مِنْهُ دِرْعًا مِنْ حَدِيدٍ‏.

Narrated By 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 armour to him."