حَدَّثَنَا حُمَيْدُ بْنُ مَسْعَدَةَ، وَأَبُو بَكْرِ بْنُ خَلاَّدٍ قَالاَ حَدَّثَنَا نُوحُ بْنُ قَيْسٍ، حَدَّثَنَا عَمْرُو بْنُ مَالِكٍ، عَنْ أَبِي الْجَوْزَاءِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ كَانَتِ امْرَأَةٌ تُصَلِّي خَلْفَ النَّبِيِّ ـ صلى الله عليه وسلم ـ حَسْنَاءُ مِنْ أَحْسَنِ النَّاسِ فَكَانَ بَعْضُ الْقَوْمِ يَسْتَقْدِمُ فِي الصَّفِّ الأَوَّلِ لِئَلاَّ يَرَاهَا وَيَسْتَأْخِرُ بَعْضُهُمْ حَتَّى يَكُونَ فِي الصَّفِّ الْمُؤَخَّرِ فَإِذَا رَكَعَ قَالَ هَكَذَا يَنْظُرُ مِنْ تَحْتِ إِبْطِهِ فَأَنْزَلَ اللَّهُ ‏ End hadith 6‏ فِي شَأْنِهَا ‏.‏

It wasnarrated that Ibn ‘Abbas said: “A woman used to perform prayerbehind the Prophet (PBUH), and she was one of the most beautiful ofpeople. Some of the people used to go into the first row so that theywould not see her, and some of them used to lag behind so that theywould be in the last row, and when they bowed, they would do likethisso that they could see her from beneath their armpits. ThenAllahrevealed: “And indeed, We know the first generations of youwho hadpassed away, and indeed, We know the present generations ofyou(mankind), and also those who will some afterwards.” [15:24]concerning her matter. Translation Not Available

Book Ref: Sunan Ibn Majah Book 5 Hadith 1046
Web Ref:  Sunan Ibn Majah Vol 1 Book 5 Hadith 1046