The Messenger of Allah (may Allah's peace and blessings be upon him) bought food from a Jew and pledged him his iron armor

Explanation

The Prophet (may Allah's peace and blessings be upon him) bought barley to serve as food from a Jew, and pawned his coat of mail that he needed for Jihad with him. The Prophet (may Allah's peace and blessings be upon him) used to wear that armor in war to give himself extra protection from the enemy's weapons.