A Sahabi once came to Rasulullah (Sallallahu Alaihi Wasallam) and complained of hunger and distress. At that time Rasulullah (Sallallahu Alaihi Wasallam) had nothing with him to present to the guest. Subsequently, Rasulullah (Sallallahu Alaihi Wasallam) sent a message to his blessed wives, enquiring from them as to whether they had anything to offer the guest. Each wife informed that there was nothing in their home besides water. Nabi (Sallallahu Alaihi Wasallam) thereafter addressed the Sahabah (Radhiallahu Anhum) saying: "Who among you will entertain the guest tonight on my behalf?"
Abu Talhah (Radhiallahu Anhu), an Ansaari Sahaabi said: “O Messenger of Allah (Sallallahu Alaihi Wasallam), I will host him."
The Ansaari took the person to his house and told his wife: "The person I have brought home is the guest of Rasulullah (Sallallahu Alaihi Wasallam). We will entertain him to the best of our ability, and we will not spare anything in doing so."
The wife replied: "By Allah! We have no food in the house, except a little which is enough for the children."
The Ansaari said: "You put the children off to sleep without feeding them (since they are not hungry), while I sit with the guest over the meal. When we start eating, extinguish the lamp pretending to set it right, so that the guest may not become aware of my not sharing the meal with him."
The plan worked out well, and that night the entire family went to sleep without eating allowing the guest to eat to his fill. It was on that occasion that the following verse was revealed:
يُؤْثِرُونَ عَلَىٰ أَنفُسِهِمْ وَلَوْ كَانَ بِهِمْ خَصَاصَةٌ
"They prefer others above themselves, though poverty be their lot. (Surah Hashr)." [1]
[1]Bukhari Sharif, Malfoozaat Faqeehil Ummah