What lesson did the Prophet Muhammad (saw) teach about how believers should interact with one another?
 Narrated Abu Musa:                     The Prophet said, "A believer to another believer is like a building whose different parts enforce each other." The Prophet then clasped his hands with the fingers interlaced. (At that time) the Prophet was sitting and a man came and begged or asked for something. The Prophet faced us and said, "Help and recommend him and you will receive the reward for it, and Allah will bring about what He will through His Prophet's tongue."