Musnad Ahmad 32:726

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from Abu 'Uthman, from Anas, who said: When the Prophet, may God bless him and grant him peace, married Zaynab, Umm Sulaym gifted him *hays* (a dish of dates, ghee, and dried yogurt) in a stone bowl. Anas said: The Prophet, may God bless him and grant him peace, said: "Go and invite whomever you meet." So I invited for him whomever I met. They began to enter, eat, and leave. The Prophet, may God bless him and grant him peace, placed his hand upon the food and supplicated over it, and said what God willed for him to say. I did not leave anyone I met without inviting them. They ate until they were full and left. A group of them remained and prolonged their conversation with him. The Prophet, may God bless him and grant him peace, became shy to say anything to them, so he went out and left them in the house. Then God, the Almighty and Majestic, revealed: "O you who have believed, do not enter the houses of the Prophet except when you are permitted for a meal, without awaiting its readiness. But when you are invited, then enter," until He reached, "for your hearts and their hearts."