A man named Abu Shuayb came to a young slave of his who was a butcher and said, "Prepare for me food enough for five, for I have seen hunger on the face of the Messenger of Allah ﷺ."So the slave prepared the food, then Abu Shuayb sent word to the Prophet ﷺ inviting him along with the companions who were sitting with him. When the Prophet ﷺ got up to go, another man followed them who had not been among those invited. When the Messenger of Allah ﷺ reached the door, he said to the host, "A man has followed us who was not with us when you invited us. If you permit him, he may enter."The host replied, "We give him permission, let him enter."
حدثنا هناد حدثنا أبو معاوية عن الأعمش عن شقيق
جاء رجل يقال له أبو شعيب إلى غلام له لحام فقال اصنع لي طعاما يكفي خمسة فإني رأيت في وجه رسول الله ﷺ الجوع قال فصنع طعاما ثم أرسل إلى النبي ﷺ فدعاه وجلساءه الذين معه فلما قام النبي ﷺ اتبعهم رجل لم يكن معهم حين دعوا فلما انتهى رسول الله ﷺ إلى الباب قال لصاحب المنزل إنه اتبعنا رجل لم يكن معنا حين دعوتنا فإن أذنت له دخل قال فقد أذنا له فليدخل
Sourcing, agreed upon by Bukhari and Muslim. Muslim also recorded it in the Book of Drinks, in the chapter on what a guest should do if someone other than the one who invited him follows him, and so on, hadith 2036, from the report of Abu Muawiya al-Darir. Bukhari recorded it, hadith 5434, from the host of the meal. Abu Dawud, hadith 3741, [narrated] the hadith of Amash with the same wording.On this subject there is also a report from Ibn Umar.