إِن تُبۡدُواْ ٱلصَّدَقَـٰتِ فَنِعِمَّا هِىَۖ وَإِن تُخۡفُوهَا وَتُؤۡتُوهَا ٱلۡفُقَرَآءَ فَهُوَ خَيۡرٌ۬ لَّڪُمۡۚ وَيُكَفِّرُ عَنڪُم مِّن سَيِّـَٔاتِڪُمۡۗ وَٱللَّهُ بِمَا تَعۡمَلُونَ خَبِيرٌ۬
If you disclose your Sadaqât (alms-giving), it is well, but if you conceal them, and give them to the poor, that is better for you. (Allâh) will expaite you some of your sins. And Allâh is Well-Acquainted with what you do.
[Surah Baqarah (2):271]
It is reported that Abu Al Aliyah said, “I learned writing and the Quran without my family noticing, and not a drop of ink was ever seen on my garment.”
Abû Nu’aym, Hilyatu Al-Awliyâ` Vol. 2 p217.
It is reported that when Ibn Abi Layla prayed [at night], if someone entered [his house], he would lie down on his bed [as if he was sleeping].
Ibid. Vol. 4 p351.
It is reported that Ayyûb Al-Sakhtiyânî used to pray all night and hide it. In the morning, he would raise his voice as if he had just woken up
Al-Dhahabî, op. cit. Vol. 6 p17.
It is reported that Dawud b. Abi Hind fasted for forty years without his family knowing, he would take his lunch out with him and donate it in the street.
Ibid. Vol. 6 p378.