Quran 58:3 Al-Mujadilah, ayah 3 of 22

وَٱلَّذِينَ يُظَـٰهِرُونَ مِن نِّسَآئِهِمْ ثُمَّ يَعُودُونَ لِمَا قَالُوا۟ فَتَحْرِيرُ رَقَبَةٍ مِّن قَبْلِ أَن يَتَمَآسَّا ۚ ذَٰلِكُمْ تُوعَظُونَ بِهِۦ ۚ وَٱللَّهُ بِمَا تَعْمَلُونَ خَبِيرٌ ۝٣

58:3 Those who put away their wives (by saying they are as their mothers) and afterward would go back on that which they have said, (the penalty) in that case (is) the freeing of a slave before they touch one another. Unto this ye are exhorted; and Allah is Informed of what ye do.