مَنْ تَصَدَّقَ بِعَدْلِ تَمْرَةٍ مِنْ كَسْبٍ طَيِّبٍ، وَلَا يَقْبَلُ اللَّهُ إِلَّا الطَّيِّبَ، فَإِنَّ اللَّهَ يَتَقَبَّلُهَا بِيَمِينِهِ ثُمَّ يُرَبِّيهَا لِصَاحِبِهَا كَمَا يُرَبِّي أَحَدُكُمْ فَلُوَّهُ حَتَّى تَكُونَ مِثْلَ الْجَبَلِ
Whoever gives charity equal to a date from good earnings - and Allah does not accept except what is good - Allah will accept it with His Right Hand, then He will nurture it for its owner, as one of you nurtures his foal, until it becomes like a mountain.
Abu Hurairah•Sahih Bukhari & Muslim•Charity