Sayyiduna Mu’adh bin Anas al-Juhani (may Allah be pleased with him) narrates that the Noble Prophet (peace and blessings be upon him) said: Whoever comes to a gathering, it is his duty to say salam, and whoever stands up to leave a gathering, it is also his duty to say salam when leaving. Meanwhile, a man stood up to leave, and since the Noble Prophet (peace and blessings be upon him) was still engaged in conversation, he left without saying salam. The Prophet (peace and blessings be upon him) said about him: He has forgotten the matter very quickly.