He saw the Messenger of Allah ﷺ, and the person who resembled him most was Hasan bin Ali.
حدثنا يزيد أخبرنا إسماعيل يعني ابن خالد حدثني
أنه رأى رسول الله ﷺ وكان أشبه الناس به الحسن بن علي
Its isnad is sahih. It is found in Bukhari 7/95, no. 3752, Fath, in the chapters on the virtues of the companions, the merits of Hasan and Husayn, and in Tirmidhi 5/659, no. 3777, where he said, hasan sahih.