The Book of Pilgrimage (Kitab Al-Hajj)
Muslim :: Book 7 : Hadith 2914
Abdullah b. Sarjis reported: I saw the bald one, i. e. 'Umar b. Khattib (Allah be pleased with him). kissing the Stone and saying: By Allah. I am kissing with full consciousness of the fact that you are a stone and that you can neither do any harm nor good; and if I had not seen Allah's Messenger (may peace be upon him) kissing you. I would not have kissed you. The rest of the hadith is the same.