The Messenger of Allah ﷺ said, "When one of you is invited to a meal and comes along with the messenger, that itself serves as his permission to enter."
أن رسول الله ﷺ قال: إذا دعي أحدكم إلى طعام، فجاء مع الرسول، فإن ذلك له إذن.
Reported by Abu Dawud (5190), Bukhari in Adab al-Mufrad (1075), and Imam Ahmad (10894), all of them from the hadith of Abdul-Ala, who said, Saeed narrated to us, from Qatada, from Abu Rafi, from Abu Hurairah, and he mentioned it. Its chain of transmission is sahih.