Those who make Sadaqah do not decrease in their wealth, but Allah increases the wealth of those who are generous in their charity.
قُل لِّعِبَادِيَ الَّذِينَ آمَنُوا يُقِيمُوا الصَّلَاةَ وَيُنفِقُوا مِمَّا رَزَقْنَاهُمْ سِرًّا وَعَلَانِيَةً مِّن قَبْلِ أَن يَأْتِيَ يَوْمٌ لَّا بَيْعٌ فِيهِ وَلَا خِلَالٌ
(O Prophet!) Tell those of My servants who believe that they should establish Prayer and spend out of what We have provided them with, both secretly and openly, before there arrives the Day when there will be no bargaining, nor any mutual befriending. (14:31)