It is narrated from Sa'id bin al-Musayyib that when Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) became Caliph, he stood on the pulpit of the Messenger of Allah (peace and blessings be upon him) and addressed the people. After praising and extolling Allah, he said: O people, I know that you perceive harshness and severity in me. The reason is that I was with the Messenger of Allah (peace and blessings be upon him) and was his servant and slave, and he (peace and blessings be upon him) was, as Allah has said, "most kind and merciful to the believers." I was before him like a drawn sword (I was strict), except when he (peace and blessings be upon him) would sheathe me or stop me, and then I would hold back; otherwise, because of his gentleness, I would be severe with people. The chain of this hadith is sahih; Imam Bukhari used Abu Salih as evidence, and although Sa'id's hearing from Umar (may Allah be pleased with him) is disputed, according to most Imams it is established.