Quran An-Nur 24:8
وَيَدۡرَؤُاْ عَنۡهَا ٱلۡعَذَابَ أَن تَشۡهَدَ أَرۡبَعَ شَهَٰدَٰتِۭ بِٱللَّهِ إِنَّهُۥ لَمِنَ ٱلۡكَٰذِبِينَ
Translation
But it will prevent punishment from her if she gives four testimonies [swearing] by Allāh that indeed, he is of the liars.