Jami` at-Tirmidhi 1099
Abu Mas'ud narrated:
"A man named Abu Shu'aib came to a slave of his, who was a butcher, and said: 'Prepare some food for me that will be sufficient for five, for I have seen hunger in the face of the Messenger of Allah.' So he prepared some food. Then he sent a message to the Prophet inviting him and those who were sitting with him. When the Prophet stood, he was followed by a man who was not with them when they were invited. When the Messenger of Allah arrive at the door he said to the owner of the house: 'A man who was not with us when you invited us followed us, if you permit him, he will enter.'" He said: We have permitted him, let him enter."
حَدَّثَنَا هَنَّادٌ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ شَقِيقٍ، عَنْ أَبِي مَسْعُودٍ، قَالَ جَاءَ رَجُلٌ يُقَالُ لَهُ أَبُو شُعَيْبٍ إِلَى غُلاَمٍ لَهُ لَحَّامٍ فَقَالَ اصْنَعْ لِي طَعَامًا يَكْفِي خَمْسَةً فَإِنِّي رَأَيْتُ فِي وَجْهِ رَسُولِ اللَّهِ صلى الله عليه وسلم الْجُوعَ ‏.‏ قَالَ فَصَنَعَ طَعَامًا ثُمَّ أَرْسَلَ إِلَى النَّبِيِّ صلى الله عليه وسلم فَدَعَاهُ وَجُلَسَاءَهُ الَّذِينَ مَعَهُ فَلَمَّا قَامَ النَّبِيُّ صلى الله عليه وسلم اتَّبَعَهُمْ رَجُلٌ لَمْ يَكُنْ مَعَهُمْ حِينَ دُعُوا فَلَمَّا انْتَهَى رَسُولُ اللَّهِ صلى الله عليه وسلم إِلَى الْبَابِ قَالَ لِصَاحِبِ الْمَنْزِلِ ‏
"‏ إِنَّهُ اتَّبَعَنَا رَجُلٌ لَمْ يَكُنْ مَعَنَا حِينَ دَعَوْتَنَا فَإِنْ أَذِنْتَ لَهُ دَخَلَ ‏"‏ ‏.‏ قَالَ فَقَدْ أَذِنَّا لَهُ فَلْيَدْخُلْ ‏.‏ قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ ‏.‏ قَالَ وَفِي الْبَابِ عَنِ ابْنِ عُمَرَ ‏.‏