Quran 2:271 — The Heifer (Al-Baqarah)

If you declare your charities, they are still good. But if you keep them anonymous, and give them to the poor, it is better for you, and remits more of your sins. GOD is fully Cognizant of everything you do.

[2:270] Any charity you give, or a charitable pledge you fulfill, GOD is fully aware thereof. As for the wicked, they will have no helpers.

[2:272] You are not responsible for guiding anyone. GOD is the only one who guides whoever chooses (to be guided). Any charity you give is for your own good. Any charity you give shall be for the sake of GOD. Any charity you give will be repaid to you, without the least injustice.