Once, Hazrat Awf bin Malik (may Allah be pleased with him) and Dhu’l-Kila’ entered the Al-Aqsa Mosque, that is, Bayt al-Maqdis. Hazrat Awf (may Allah be pleased with him) said to him, “You have your nephew (Ka’b Ahbar) with you.” Dhu’l-Kila’ said, “He is the best man among all people.” Hazrat Awf (may Allah be pleased with him) said, “I bear witness that I heard the Noble Prophet (peace and blessings be upon him) say: Only he may deliver admonition who is a leader, or has been given its command and permission, or else he is being pretentious (showing off).”
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 23972