Abū Hurairah relates that (once) a man came to the Holy Messenger (peace and blessings of Allah be to him) and submitted: I am much hungry. The Holy Messenger sent word to one of his wives (if she could feed the guest). She replied: ‘By Allah Who has sent you with the Truth, I have nothing except water.’ Then he sent message to another wife and got the same reply. He sent word turn by turn to everyone of them, and received the same reply (that they have nothing but water with them). Then he addressed his Companions and said, ‘Who will take this man as his guest?’ An Ansar responded: ‘O Messenger of Allah (peace and blessings of Allah be to him) ,I will.’ As such he took him home and asked his wife: ‘Entertain and honour this guest of the Holy Messenger (peace and blessings of Allah be to him).’
According to another version, he asked his wife: ‘Have you anything (eatables)?’ She said, ‘Nothing, only a little for my children.’ He said, ‘Divert them with something, and when they demand food put them to sleep; and when the guest arrives put out the lamp, and pretend as if we have also joined him in eating.’ As such they sat down and the guest ate and the hosts passed the night without food. When the Ansar went to the Holy Messenger (peace and blessings of Allah be to him) next morning, the latter told him: ‘Allah the Most Exalted was much pleased with your behaviour with your guest last night.’
(Bukhari, Muslim)