"Tell him to take her back and keep her until she becomes pure, then menstruates again and becomes pure again. Then if he wishes he may keep her, or if he wishes, he may divorce her before he touches (has intercourse with) her. This is the time when Allah, the Mighty and Sublime, has stated that women may be divorced."
أَنَّهُ طَلَّقَ امْرَأَتَهُ وَهِيَ حَائِضٌ فِي عَهْدِ رَسُولِ اللَّهِ ﷺ فَسَأَلَ عُمَرُ بْنُ الْخَطَّابِ ؓ رَسُولَ اللَّهِ ﷺ عَنْ ذَلِكَ فَقَالَ رَسُولُ اللَّهِ ﷺ مُرْهُ فَلْيُرَاجِعْهَا ثُمَّ لْيُمْسِكْهَا حَتَّى تَطْهُرَ ثُمَّ تَحِيضَ ثُمَّ تَطْهُرَ ثُمَّ إِنْ شَاءَ أَمْسَكَ بَعْدُ وَإِنْ شَاءَ طَلَّقَ قَبْلَ أَنْ يَمَسَّ فَتِلْكَ الْعِدَّةُ الَّتِي أَمَرَ اللَّهُ ﷻ أَنْ تُطَلَّقَ لَهَا النِّسَاءُ