(60) باب تَقْبِيلِ الْحَجَرِ
Narrated Zaid bin Aslam that his father said:
"I saw `Umar bin Al-Khattab kissing the Black Stone and he then said, (to it) 'Had I not seen Allah's Apostle kissing you, (stone) I would not have kissed you.' "
Reference: Sahih al-Bukhari 1610
In-book reference: Book 25, Hadith 96
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 2, Book 26, Hadith 679