Jabir bin Abdullah reported,

The Prophet ﷺ, when he bowed in prayer, would say, "O Allah, to You I have bowed, in You I have believed, to You I have submitted, and upon You I have relied. You are my Lord. My hearing, my sight, my blood, my flesh, my bones, and my sinews are humbled before Allah, Lord of the worlds."

Azami 11005

Sahih

عن جابر بن عبد الله

عن النبي ﷺ كان إذا ركع قال: اللهم لك ركعت، وبك آمنت، ولك أسلمت، وعليك توكلت، أنت ربي، خشع سمعي وبصري ودمي ولحمي وعظمي وعصبي الله رب العالمين.

الأعظمي 11005صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Supplications, remembrances, and prayer upon the chosen Prophet ﷺ
Chapter
Supplications of adhan and prayer, and what is related to them
Section
What is said in ruku and sujud
Numbering
Jami al-Kamil 11005 (2nd edition)
Azami 11005