(Imām Bukhārī narrates): Muhammad narrated to us, he said: 'Abdah informed us, from Yahyā ibn Sa'īd al-Ansārī, from 'Amrah, from 'Ā'ishah, may Allāh be pleased with her, she narrated that:
the Messenger of Allāh ﷺ used to pray at night in a chamber, and the wall of the chamber was low. So the people saw the Prophet ﷺ, then the people began to pray with the Prophet ﷺ. So in the morning they mentioned this event. So the Prophet ﷺ also stood (in prayer) the next night; the people again prayed with his prayer. They did this for two nights or three nights, until after that the Messenger of Allāh ﷺ sat down, and did not come out for the prayer. Then when morning came, the people mentioned it, so he said: I feared that the night prayer would be made obligatory upon you.
حَدَّثَنَا مُحَمَّدٌ، قَالَ أَخْبَرَنَا عَبْدَةُ، عَنْ يَحْيَى بْنِ سَعِيدٍ الأَنْصَارِيِّ، عَنْ عَمْرَةَ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُصَلِّي مِنَ اللَّيْلِ فِي حُجْرَتِهِ، وَجِدَارُ الْحُجْرَةِ قَصِيرٌ، فَرَأَى النَّاسُ شَخْصَ النَّبِيِّ صلى الله عليه وسلم فَقَامَ أُنَاسٌ يُصَلُّونَ بِصَلاَتِهِ، فَأَصْبَحُوا فَتَحَدَّثُوا بِذَلِكَ، فَقَامَ لَيْلَةَ الثَّانِيَةِ، فَقَامَ مَعَهُ أُنَاسٌ يُصَلُّونَ بِصَلاَتِهِ، صَنَعُوا ذَلِكَ لَيْلَتَيْنِ أَوْ ثَلاَثَةً، حَتَّى إِذَا كَانَ بَعْدَ ذَلِكَ جَلَسَ رَسُولُ اللَّهِ صلى الله عليه وسلم فَلَمْ يَخْرُجْ، فَلَمَّا أَصْبَحَ ذَكَرَ ذَلِكَ النَّاسُ فَقَالَ " إِنِّي خَشِيتُ أَنْ تُكْتَبَ عَلَيْكُمْ صَلاَةُ اللَّيْلِ ".
Reference: Sahih Al Bukhari 729