Quran 24:23

إِنَّ ٱلَّذِينَ يَرۡمُونَ ٱلۡمُحۡصَنَـٰتِ ٱلۡغَـٰفِلَـٰتِ ٱلۡمُؤۡمِنَـٰتِ لُعِنُواْ فِى ٱلدُّنۡيَا وَٱلۡأَخِرَةِ وَلَهُمۡ عَذَابٌ عَظِيمٌ۬ ٢٣

Surely, those who falsely accuse married women who are pious believers have incurred condemnation in this life and in the Hereafter; they have incurred a horrendous retribution.