عَنْ يَعْلَى بْنِ مَمْلَكٍ أَنَّهُ سَأَلَ أُمَّ سَلَمَةَ رَضِيَ اللَّهُ عَنْهَا زَوْجَ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ عَنْ صَلَاةِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ بِاللَّيْلِ قَالَتْ كَانَ يُصَلِّي الْعِشَاءَ الْآخِرَةَ ثُمَّ يُسَبِّحُ ثُمَّ يُصَلِّي بَعْدَهَا مَا شَاءَ اللَّهُ مِنَ اللَّيْلِ ثُمَّ يَنْصَرِفُ فَيَرْقُدُ مِثْلَ مَا صَلَّى ثُمَّ يَسْتَيْقِظُ مِنْ نَوْمَتِهِ تِلْكَ فَيُصَلِّي مِثْلَ مَا نَامَ وَصَلَاتُهُ الْآخِرَةُ تَكُونُ إِلَى الصُّبْحِ
It is narrated from Ya'la bin Mamlak that he inquired from the wife of the Messenger, Sayyida Umm Salama (may Allah be pleased with her), about the night prayer of the Prophet Muhammad (peace and blessings be upon him). She replied: After performing the 'Isha prayer, the Prophet (peace and blessings be upon him) would offer voluntary prayers, and then during the night, he would pray as much as Allah granted him the ability. After that, he (peace and blessings be upon him) would move away from the prayer mat and sleep for about as long as he had stood in prayer. Then, upon waking from sleep, he would stand in prayer again for about the same duration. This routine of the Prophet's (peace and blessings be upon him) prayer continued until morning.