مُسْنَدُ أَحْمَدَ
Musnad Ahmad 1719
The Musnad of Ahlul-Bayt & Hadeeth of al-Hasan bin 'Ali bin Abu Talib
It was narrated from Hubairah: al-Hasan bin "Ali (رضي الله عنه) addressed us and said: A man [i.e., ‘Ali] left you yesterday whom none of the early ones surpassed in knowledge and none of the later ones will ever catch up with him. The Messenger of Allah (ﷺ) would send him with the banner, Jibreel on his right side and Mika"eel on his left, and he would not give up until victory was granted to him.
Musnad Ahmad 1719Hasan; this is a da'eef isnaad]