Sahih Bukhari | Volume 3 | Hadith Number 295

Narrated by Abu Mas'ud
An Ansari man, called Abu Shu'aib, came and told his butcher slave, "Prepare meals

sufficient for five persons, for I want to invite the Prophet along with four other persons as I saw signs of hunger on his face." Abu Shu'aib invited them and another person came along with them. The Prophet said (to Abu Shu'aib), This man followed us, so if you allow him, he will join us, and if you want him to return, he will go back." Abu Shu'aib said, "No, I have allowed him (i.e. he, too, is welcomed to the meal)."