Good Manners and Form (Al-Adab)
Bukhari :: Book 8 :: Volume 73 :: Hadith 112
Narrated Jarir:
The Prophet did not screen himself from me (had never prevented me from entering upon him) since I embraced Islam, and whenever he saw me, he would receive me with a smile. Once I told him that I could not sit firm on horses. He stroked me on the chest with his hand, and said, "O Allah! Make him firm and make him a guiding and a rightly guided man.