Qays bin Ubad narrates: I was standing in prayer in the first row in the mosque at Madinah when a man pulled me from behind, moved me aside and stood in my place himself. When he finished the prayer, it turned out that he was Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him). He said: O young man, may Allah not grieve you; this was the instruction of the Messenger of Allah (peace and blessings be upon him) to us, that we (the people of knowledge) should stay close to him. Then he faced the qiblah and said three times: By the Lord of the Ka'bah, the people of authority and management (the rulers) have perished! I do not grieve for them; rather, I grieve for those whom they have led astray. This hadith is sahih (authentic) on the condition of Imam Bukhari, but they did not record it; Yusuf bin Ya'qub al-Sadusi is a trustworthy narrator of Bukhari.