Hubayrah bin Yarim said: I heard Sayyiduna al-Hasan bin Ali (may Allah be pleased with him) addressing the people, and he said: "O people! Yesterday a man departed from you whom those before did not surpass in knowledge, and whom those after will not attain. The Messenger of Allah (peace and blessings be upon him) would send him on a mission and give him the banner, and he would not return until Allah granted him victory. Jibril would be on his right and Mika'il on his left. He left behind no gold or silver except seven hundred dirhams, with which he wanted to buy a servant."
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2706