When you visit your Muslim brother and he serves you food, eat it without asking about it, and when he gives you a drink, drink it without asking about it.
إذا دخلت على أخيك المسلم فأطعمك طعاما فكل، ولا تسأله وإذا سقاك شرابا فاشربه، ولا تسأله.
No references are available.
Hakim reported it (4/126) from Abu Bakr bin Ishaq, who reported that Bishr bin Musa told them, Humaydi told them, Sufyan told them, from Ibn Ajlan, from Saeed, from Abu Hurairah, and he related it. Its chain is hasan because of Ibn Ajlan, for his hadith is hasan.Ahmad (9184) and Hakim (4/126) both reported it through the route of Muslim bin Khalid, from Zayd bin Aslam, from Sumayy (who is the freed servant of Abu Bakr bin Abdul-Rahman bin Harith), from Abu Salih, from Abu Hurairah, and he related something similar.Hakim said, "This is a hadith sahih in its chain, and the two of them (Bukhari and Muslim) did not include it, and it has a sahih corroborating witness that meets the standard of Muslim alone." Then he traced it through the earlier route of Abu Bakr.I say, in this chain is Muslim bin Khalid Zanji, and he has poor memory, but there is no harm in him for corroborations and supporting witnesses.