Sayyiduna Sa’d bin Abi Waqqas (may Allah be pleased with him) narrates: On the occasion of the Battle of Tabuk, the Prophet Muhammad (peace and blessings be upon him) appointed Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) as the (guardian) of Madinah in his absence. So he said: O Messenger of Allah! Are you leaving me behind among children and women? The Prophet Muhammad (peace and blessings be upon him) said: Are you not pleased that your relation to me is like that of Sayyiduna Harun (Aaron) (peace be upon him) to Sayyiduna Musa (Moses) (peace be upon him)? However, there will be no prophet after me.