(Annoor) 24 : 6
وَالَّذِينَ يَرْمُونَ أَزْوَاجَهُمْ وَلَمْ يَكُنْ لَهُمْ شُهَدَاءُ إِلَّا أَنْفُسُهُمْ فَشَهَادَةُ أَحَدِهِمْ أَرْبَعُ شَهَادَاتٍ بِاللَّهِ ۙ إِنَّهُ لَمِنَ الصَّادِقِينَ
And those who accuse their wives and have no witnesses except themselves, then each of them should testify 4 times with the Lord Allah that indeed, he is among the truthful.