Sunan al-Nasa'i
The Book of The At-Tatbiq (Clasping One's Hands Together) — Hadith #1053
أَخْبَرَنَا يَحْيَى بْنُ عُثْمَانَ الْحِمْصِيُّ، قَالَ حَدَّثَنَا أَبُو حَيْوَةَ، قَالَ حَدَّثَنَا شُعَيْبٌ، عَنْ مُحَمَّدِ بْنِ الْمُنْكَدِرِ، عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ، عَنِ النَّبِيِّ صلى الله عليه وسلم كَانَ إِذَا رَكَعَ قَالَ
" اللَّهُمَّ لَكَ رَكَعْتُ وَبِكَ آمَنْتُ وَلَكَ أَسْلَمْتُ وَعَلَيْكَ تَوَكَّلْتُ أَنْتَ رَبِّي خَشَعَ سَمْعِي وَبَصَرِي وَدَمِي وَلَحْمِي وَعَظْمِي وَعَصَبِي لِلَّهِ رَبِّ الْعَالَمِينَ " .
When the Prophet (ﷺ) bowed, he said: “Allahumma laka rak’atu wa bika amantu wa laka aslamtu wa alayka tawwakaltu, anta Rabbi, khasha’a sam’i wa basri wa dammi wa lahmi wa ‘azmi wa ‘asabi Lillahi Rabbil-‘Alamin ( O Allah, to You I have bowed, in You I believe, to You I have submitted and in You I put my trust. You are my Lord. My hearing, my sight, my blood, my flesh, my bones and sinews are humbled before Allah, the Lord of the Worlds.)”
Chain of Narration (Isnad)