عَنْ عَبْدِ اللَّهِ بْنِ أَبِي قَيْسٍ عَنْ عَائِشَةَ زَوْجِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ وَرَضِيَ عَنْهَا قَالَتْ: عَلَيْكُمْ بِقِيَامِ اللَّيْلِ، فَإِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ كَانَ لَا يَدَعُهُ، فَإِنْ مَرِضَ قَرَأَ وَهُوَ قَاعِدٍ، وَقَدْ عَرَفْتُ أَنَّ أَحَدَكُمْ يَقُولُ بِحَسْبِي أَنْ أُقِيمَ مَا كُتِبَ لِي، وَأَنَّى لَهُ ذَلِكَ
The wife of the Messenger, Sayyida Aisha (may Allah be pleased with her), narrates: She says, "Be diligent in standing for prayer at night, because the Messenger of Allah (peace and blessings be upon him) never abandoned it. If he was ill, he would perform this prayer while sitting. I know that you say, 'We will only pray as much as has been decreed for us,' but then how will it attain its status?"