al-Khlyl bin 'Amr al-Thqfy الخليل بن عمرو الثقفي · Chapters on Hajj Rituals

“I saw the bald forehead of ‘Umar bin Khattab when he kissed the Black Stone and said: ‘I am kissing you, although I know that you are only a stone and you can neither cause harm nor bring benefit. Had I not seen the Messenger of Allah (ﷺ) kissing you, I would not have kissed you.’”