Mishkat al-Masabih

‘Abdallah b. ‘Amr said:I was told that God’s Messenger had said, “Prayer engaged in by a man while sitting counts as half the prayer,” so I went to him and I found him praying while sitting, and I put my hand on his head. He said, “What is the matter with you, ‘Abdallah b. ‘Amr? ’’ I replied, “I have been told, Messenger of God, that you said that prayer engaged in by a man while sitting counts as half the prayer, yet you yourself are praying while sitting.” He said, “Yes, but I am not like one of you.” Muslim transmitted it.