Sahih al-Bukhari 46:17
Narrated Abu Mas`ud:
There was an Ansari man called Abu Shu'aib who had a slave butcher. Abu Shu'aib said to him, "Prepare a meal sufficient for five persons so that I might invite the Prophet (ﷺ) besides other four persons." Abu Shu'aib had seen the signs of hunger on the face of the Prophet (ﷺ) and so he invited him. Another man who was not invited, followed the Prophet. The Prophet (ﷺ) said to Abu Shu'aib, "This man has followed us. Do you allow him to share the meal?" Abu Shu'aib said, "Yes."
Reference
Sahih al-Bukhari 46:17
In-book reference
Book 46, Hadith 17
Arabic Text
حَدَّثَنَا أَبُو النُّعْمَانِ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي وَائِلٍ، عَنْ أَبِي مَسْعُودٍ، أَنَّ رَجُلاً، مِنَ الأَنْصَارِ يُقَالُ لَهُ أَبُو شُعَيْبٍ كَانَ لَهُ غُلاَمٌ لَحَّامٌ فَقَالَ لَهُ أَبُو شُعَيْبٍ اصْنَعْ لِي طَعَامَ خَمْسَةٍ لَعَلِّي أَدْعُو النَّبِيَّ صلى الله عليه وسلم خَامِسَ خَمْسَةٍ. وَأَبْصَرَ فِي وَجْهِ النَّبِيِّ صلى الله عليه وسلم الْجُوعَ ـ فَدَعَاهُ، فَتَبِعَهُمْ رَجُلٌ لَمْ يُدْعَ فَقَالَ النَّبِيُّ صلى الله عليه وسلم " إِنَّ هَذَا قَدِ اتَّبَعَنَا أَتَأْذَنُ لَهُ ". قَالَ نَعَمْ.