ALI 'IMRAN — Ayat 135

وَالَّذِينَ إِذَا فَعَلُواْ فَاحِشَةً أَوْ ظَلَمُواْ أَنْفُسَهُمْ ذَكَرُواْ اللّهَ فَاسْتَغْفَرُواْ لِذُنُوبِهِمْ وَمَن يَغْفِرُ الذُّنُوبَ إِلاَّ اللّهُ وَلَمْ يُصِرُّواْ عَلَى مَا فَعَلُواْ وَهُمْ يَعْلَمُونَ

And those who, when they commit an immorality or wrong themselves [by transgression], remember Allah and seek forgiveness for their sins - and who can forgive sins except Allah ? - and [who] do not persist in what they have done while they know.