WE RELATE FROM the Ṣaḥīḥs of al-Bukhārī and Muslim that Abū Hurayrah 
narrated that a man came to the Messenger of Allah 
and said: “I am in need.” The Messenger of Allah sent for one of his wives, but she said: “By Him Who has sent you with the truth, I do not have anything but water.” He sent for another and she said the same, until all of them had said the same. [The Prophet ] asked: “Who will entertain this man tonight, and Allah will have mercy on him?” One of the Anṣār stood up and said: “I, Messenger of Allah.” He went with him to his house and asked his wife: “Do you have anything?” She replied: “No, except for the children’s food.” He said: “Put the children to sleep with something, and when our guest enters put out the lamp and make it appear to him as if we are eating. When he sits down to eat then go and get the lamp and extinguish it.” They sat down, and the guest ate. When he got up in the morning he went to the Messenger of Allah , who said: “Allah was pleased with what the two of you did for your guest. Allah 
revealed this verse: ‘They give others preference over themselves, even though poverty be their own lot.’” [1].
narrated that a man came to the Messenger of Allah and said: “I am in need.” The Messenger of Allah sent for one of his wives, but she said: “By Him Who has sent you with the truth, I do not have anything but water.” He sent for another and she said the same, until all of them had said the same. [The Prophet ] asked: “Who will entertain this man tonight, and Allah will have mercy on him?” One of the Anṣār stood up and said: “I, Messenger of Allah.” He went with him to his house and asked his wife: “Do you have anything?” She replied: “No, except for the children’s food.” He said: “Put the children to sleep with something, and when our guest enters put out the lamp and make it appear to him as if we are eating. When he sits down to eat then go and get the lamp and extinguish it.” They sat down, and the guest ate. When he got up in the morning he went to the Messenger of Allah , who said: “Allah was pleased with what the two of you did for your guest. Allah revealed this verse: ‘They give others preference over themselves, even though poverty be their own lot.’” [1].
I say: “This is taken to mean that the children did not have a crucial need for the food, because normally children will demand food, even if they are not hungry, when they see others eat. It also means that the man and woman gave preference to their guest. And Allah knows best.”
References
[1] Qur’ān 59:9. Al-Bukhārī (3798), and Muslim (2053).