[Machine] There was a woman who used to pray behind the Prophet ﷺ and she was the most beautiful of all people. Some men were in the back rows and they looked at her. One of them used to look at her from under his armpit, and another one used to move forward to the first row so that he could not see her. Then Allah revealed this verse: "And We certainly know those who are ahead of you from among you and We certainly know those who are behind you." [Al-Hijr 24]  

كَانَتِ امْرَأَةٌ تُصَلِّي خَلْفَ النَّبِيِّ ﷺ أَجْمَلَ النَّاسِ فَكَانَ نَاسٌ فِي آخِرِ صُفُوفِ الرِّجَالِ فَنَظَرُوا إِلَيْهَا قَالَ وَكَانَ أَحَدُهُمْ يَنْظُرُ إِلَيْهَا مِنْ تَحْتِ إِبْطِهِ وَكَانَ أَحَدُهُمْ يَتَقَدَّمُ إِلَى الصَّفِّ الْأَوَّلِ لَا يَرَاهَا فَأَنْزَلَ اللهُ ﷻ هَذِهِ الْآيَةَ {وَلَقَدْ عَلِمْنَا الْمُسْتَقْدِمِينَ مِنْكُمْ وَلَقَدْ عَلِمْنَا الْمُسْتَأْخِرِينَ} [الحجر 24]  

“A woman used to perform prayer behind the Prophet ﷺ, and she was one of the most beautiful of people. Some of the people used to go into the first row so that they would not see her, and some of them used to lag behind so that they would be in the last row, and when they bowed, they would do like this so that they could see her from beneath their armpits. Then Allah revealed: “And indeed, We know the first generations of you who had passed away, and indeed, We know the present generations of you (mankind), and also those who will some afterwards.” [15:24] concerning her matter. (Using translation from Ibn Mājah 1046)   

أَنَّهُ قَالَ كَانَتْ تُصَلِّي خَلْفَ رَسُولِ اللهِ ﷺ امْرَأَةٌ حَسْنَاءُ مِنْ أَحْسَنِ النَّاسِ وَكَانَ بَعْضُ الْقَوْمِ يَسْتَقْدِمُ فِي الصَّفِّ الْأَوَّلِ لِئَلَّا يَرَاهَا وَيَسْتَأْخِرُ بَعْضُهُمْ حَتَّى يَكُونَ فِي الصَّفِّ الْمُؤَخَّرِ فَإِذَا رَكَعَ قَالَ هَكَذَا وَنَظَرَ مِنْ تَحْتِ إِبْطِهِ وَجَافَى يَدَهُ فَأَنْزَلَ اللهُ تَبَارَكَ وَتَعَالَى فِي شَأْنِهَا {وَلَقَدْ عَلِمْنَا الْمُسْتَقْدِمِينَ مِنْكُمْ وَلَقَدْ عَلِمْنَا الْمُسْتَأْخِرِينَ} [الحجر 24]