(Al Hadeed) 57 : 18
إِنَّ الْمُصَّدِّقِينَ وَالْمُصَّدِّقَاتِ وَأَقْرَضُوا اللَّهَ قَرْضًا حَسَنًا يُضَاعَفُ لَهُمْ وَلَهُمْ أَجْرٌ كَرِيمٌ
Indeed the men testifying the Truth and the women testifying the Truth, and who are lending a best loan to Allah, it will be increased to them in manifold, and for them have noble reward.
See explanation 33: 35; 49: 15; 57: 11; and 61: 14.