Ali b. Abū Tālib (raḍiy Allāhu ‘anhu) narrates: “When the Messenger of Allah ﷺ would stand for prayer, he would say:
وَجَّهْتُ وَجْهِيَ لِلَّذِي فَطَرَ السَّمَوَاتِ وَالأَرْضَ حَنِيفًا وَمَا أَنَا مِنَ الْمُشْرِكِينَ إِنَّ صَلاَتِي وَنُسُكِي وَمَحْيَاىَ وَمَمَاتِي لِلَّهِ رَبِّ الْعَالَمِينَ لاَ شَرِيكَ لَهُ وَبِذَلِكَ أُمِرْتُ وَأَنَا مِنَ الْمُسْلِمِينَ
(I have turned my face towards the One who created the heavens and the earth, turned away from all that is false having surrendered to Allah, and I am not of the polytheists. My ṣalāh, my sacrifice, my life and my death are all for Allah, Lord of the worlds, who has no partners. I have been commanded of this, and I am of those who submit.)
He would then say [the above].
When he would do rukū, he would say:
اللَّهُمَّ لَكَ رَكَعْتُ وَبِكَ آمَنْتُ وَلَكَ أَسْلَمْتُ خَشَعَ لَكَ سَمْعِي وَبَصَرِي وَمُخِّي وَعَظْمِي وَعَصَبِي
(O Allah, for You Alone I have bowed in prayer, in You Alone I have believed, and to You Alone I have submitted. My hearing, sight, mind, bones and nerves are humble to You.)
When he would raise his head from rukū, he would say:
اللَّهُمَّ رَبَّنَا لَكَ الْحَمْدُ مِلْءَ السَّمَوَاتِ وَمِلْءَ الأَرْضِ وَمِلْءَ مَا بَيْنَهُمَا وَمِلْءَ مَا شِئْتَ مِنْ شَىْءٍ بَعْدُ
(O Allah, Our Lord, for You Alone is all praise; praise which fills the heavens, which fills the earth, which fills whatever is in between them, and which fills whatever You wish after that.)
When he would do sajdah, he would say:
اللَّهُمَّ لَكَ سَجَدْتُ وَبِكَ آمَنْتُ وَلَكَ أَسْلَمْتُ سَجَدَ وَجْهِي لِلَّذِي خَلَقَهُ وَصَوَّرَهُ وَشَقَّ سَمْعَهُ وَبَصَرَهُ تَبَارَكَ اللَّهُ أَحْسَنُ الْخَالِقِينَ
(O Allah, for You Alone I have prostrated, in You Alone I have believed, and to You Alone I have submitted. My face has prostrated to the One who created and fashioned it, and who formed its hearing and sight. Blessed is Allah, the Best of Creators.)
The last thing he would say after the tashahhud and the salām would be:
اللَّهُمَّ اغْفِرْ لِي مَا قَدَّمْتُ وَمَا أَخَّرْتُ وَمَا أَسْرَرْتُ وَمَا أَعْلَنْتُ وَمَا أَسْرَفْتُ وَمَا أَنْتَ أَعْلَمُ بِهِ مِنِّي أَنْتَ الْمُقَدِّمُ وَأَنْتَ الْمُؤَخِّرُ لاَ إِلَهَ إِلاَّ أَنْتَ
(O Allah, forgive me for what I have done in the past and for what I am yet to do, for what I have done privately and for what I have done publicly, for my excesses and for that which You know more than me. You are the One who brings forward and the One who puts behind, and there is no god worthy of worship except You.)
(Muslim 771)