Sahih al-Bukhari, Hadith 1597 ⓘ
Narrated `Abis bin Rabi`a: `Umar came near the Black Stone and kissed it and said "No doubt, I know that you are a stone and can neither benefit anyone nor harm anyone. Had I not seen Allah's Messenger kissing you I would not have kissed you."
حَدَّثَنَا مُحَمَّدُ بْنُ كَثِيرٍ، أَخْبَرَنَا سُفْيَانُ، عَنِ الأَعْمَشِ، عَنْ إِبْرَاهِيمَ، عَنْ عَابِسِ بْنِ رَبِيعَةَ، عَنْ عُمَرَ ـ رضى الله عنه ـ أَنَّهُ جَاءَ إِلَى الْحَجَرِ الأَسْوَدِ فَقَبَّلَهُ، فَقَالَ إِنِّي أَعْلَمُ أَنَّكَ حَجَرٌ لاَ تَضُرُّ وَلاَ تَنْفَعُ، وَلَوْلاَ أَنِّي رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يُقَبِّلُكَ مَا قَبَّلْتُكَ.
also referenced under: Book 25, Hadith 83 (In-Book) & Volume 2, Book 26, Hadith 667 (USC-MSA)