It was narrated from Qaboos bin Abi Zabyan that his father told him: We said to Ibn 'Abbas (رضي الله عنه):

What do you think this verse means: "Allah has not made for any man two hearts inside his body" [al-Ahzab 33:41]? He said: The Prophet of Allah (ﷺ) stood up one day to pray, and he shifted his weight from one leg to another. The hypocrites who were praying with him said: Don't you see that he has two hearts, one heart with you and one heart with them? Then Allah revealed the words: "Allah has not made for any man two hearts inside his body" [al-Ahzab 33:41]