Musnad Ahmad 32:1679

'Affan narrated to us, Hammad narrated to us, he said: Humayd informed us, from Anas ibn Malik, who said: "There was no person whose sight was more beloved to them than the Messenger of Allah, may Allah bless him and grant him peace. And when they saw him, they would not stand up, because of what they knew of his dislike for that."