Once when Imam Hasan (A) and Imam Husain (A) were children they both fell ill. When the Prophet (S) found out about the illness he suggested that both his daughter Lady Fatima (A) and his son-in-law Imam Ali (A) should keep Nadhr. Nadhr is a promise that you make to Allah. Something that you will do extra for the pleasure of Allah if your wish comes true. Imam Ali (A) and Lady Fatima (A) made a Nadhr that they would fast for three days upon the recovery of their children. Even their maid Lady Fizza, who loved the children very much joined them in making Nadhr.
Allah accepted their Nadhr and both Imam Hasan (A) and Imam Husain (A) recovered from their illness. Their parents decided to fast to fulfil their promise and when the children came to know of this, they decided to fast also. On the first day of the fasting, Lady Fatima (A) prepared 5 loaves of bread to break their fast with. In the evening when the time for Salaat set in, they all prayed then sat down to break their fast. Just as they were about to eat their loaves of bread, there was a knock on the door. There stood a poor man asking for something to eat. All of them, one by one, gave their loaf of bread to the beggar. And they had just water instead.
The next day all of them fasted again. Again they were to break their fast with a loaf of bread each which had been baked that morning. And again as they were about to eat their loaf there was a knock on the door. This time it was an orphan asking for food. Although, they themselves were two days hungry, each of them gave their loaf of bread to the orphan and again slept without any food. On the third day of their fast as they sat down to break their fast, a freed captive knocked at the door asking for food. ' Although by now the family were very hungry as they had not eaten for three days, they again gave away their loaves. The next day the Prophet (S) came to their house with the good news that Allah had revealed a whole Sura called Sura Dahr in praise of the sacrifice made by this holy family.1
in Sura Dahr Allah mentions the actions of this holy family, saying:
They [are those who] fulfill [their] vows and fear a Day whose evil will be widespread.
And they give food in spite of love for it to the needy, the orphan, and the captive,
[Saying], "We feed you only for the countenance of Allah. We wish not from you reward or gratitude.
A hadith from Lady Fatima (A)
o Allah, make me content with what you have granted me. and let me be an obedient servant to you and do those actions that earn your pleasure and not do those actions that earn your anger. 3
1. Zamakhshari, Tafsir Kashaaf, Vol 4, pg 169
يُوفُونَ بِالنَّذْرِ وَيَخَافُونَ يَوْمًا كَانَ شَرُّهُ مُسْتَطِيرًا ﴿٧﴾ وَيُطْعِمُونَ الطَّعَامَ عَلَىٰ حُبِّهِ مِسْكِينًا وَيَتِيمًا وَأَسِيرًا ﴿٨﴾ إِنَّمَا نُطْعِمُكُمْ لِوَجْهِ اللَّـهِ لَا نُرِيدُ مِنكُمْ جَزَاءً وَلَا شُكُورًا ﴿
3. A'yaan al-Shi'a, v.1, p.323