Sunan an-Nasai Book 20, Hadith 1617

أَخْبَرَنَا عِصْمَةُ بْنُ الْفَضْلِ، قَالَ حَدَّثَنَا زَيْدُ بْنُ الْحُبَابِ، عَنْ مُعَاوِيَةَ بْنِ صَالِحٍ، قَالَ حَدَّثَنَا الأَزْهَرُ بْنُ سَعِيدٍ، عَنْ عَاصِمِ بْنِ حُمَيْدٍ، قَالَ سَأَلْتُ عَائِشَةَ بِمَا كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَسْتَفْتِحُ قِيَامَ اللَّيْلِ قَالَتْ لَقَدْ سَأَلْتَنِي عَنْ شَىْءٍ مَا سَأَلَنِي عَنْهُ أَحَدٌ قَبْلَكَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُكَبِّرُ عَشْرًا وَيَحْمَدُ عَشْرًا وَيُسَبِّحُ عَشْرًا وَيُهَلِّلُ عَشْرًا وَيَسْتَغْفِرُ عَشْرًا وَيَقُولُ ‏ "‏ اللَّهُمَّ اغْفِرْ لِي وَاهْدِنِي وَارْزُقْنِي وَعَافِنِي أَعُوذُ بِاللَّهِ مِنْ ضِيقِ الْمَقَامِ يَوْمَ الْقِيَامَةِ ‏"‏ ‏.‏

It was narrated that 'Asim bin Humaid said:"I asked 'Aishah with what did he- meaning the Prophet (ﷺ)- start Qiyam Al-Lail? She said: 'You have asked me something which no one before you has asked. The Messenger of Allah (ﷺ) used to say the takbir ten times, the tahmid ten times, the tasbih ten times, and the tahlil ten times, and pray for forgiveness ten times, and say: Allahummaghfirli, wahdini, warzuqni wa 'afini. A'udhu billahi min diqil-maqami yawmal-qiyamah (O Allah, forgive me, guide me, grant me provision and good health. I seek refuge with Allah from the difficulty of standing on the Day of Resurrection)