It is narrated from Sayyiduna Abu Ayyub Ansari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "It is not lawful for a Muslim to sever relations with his brother for more than three days, such that when they meet, one turns his face this way and the other turns his face that way. And the better of the two is the one who initiates the greeting of peace (salam)."