Surah Ali 'Imran Verse 171

۞ يَسْتَبْشِرُونَ بِنِعْمَةٍ مِنَ اللَّهِ وَفَضْلٍ وَأَنَّ اللَّهَ لَا يُضِيعُ أَجْرَ الْمُؤْمِنِينَ

They receive good tidings of favor from Allah and bounty and [of the fact] that Allah does not allow the reward of believers to be lost