234 – ʿĀʾishah (may Allah be pleased with her) said: “When he was in bowing or prostration, the Messenger of Allah ﷺ would say, ‘subḥānaka-llāhumma rabbanaa wa bi-ḥamdik, Allāhumma ighfir lī (Glory be to You, O Allah, our Lord, and with Your praise; O Allah, forgive me).’” Agreed upon (1).

Vocabulary of the ḥadith
– subḥānaka-llāhumma wa bi-ḥamdik: the preposition bi- in bi-ḥamdik is attached to subḥānaka, meaning, “and with Your praise I glorify You,” that is, through Your enabling grace, guidance, and favor—not by my own power or strength.
– wa bi-ḥamdik: this prepositional phrase is either a circumstantial qualifier of the doer implied in the verbal noun that has replaced its verb, with “Allāhumma rabbanaa” serving as a parenthetical clause, or it represents the coordination of one sentence with another, just like the familiar formula “subḥān Allāh wa bi-ḥamdih.”
– Allāhumma: carries the sense of “O Allah,” the final mīm replacing the vocative particle yā.

Points derived from the ḥadith
1 – Imām Aḥmad (3674) narrates through his chain from Ibn Masʿūd: “When the verse ‘When the help of Allah comes and the conquest’ (110:1) was revealed to the Messenger of Allah ﷺ, he often said while bowing, ‘subḥānaka-llāhumma rabbanaa wa bi-ḥamdik, Allāhumma ighfir lī’ three times.”
2 – This supplication is recommended in bowing and prostration, alongside ‘subḥāna rabbī al-ʿaẓīm’ during bowing and ‘subḥāna rabbī al-aʿlā’ during prostration. The Prophet ﷺ recited it in obedience to the verse, “So glorify the praise of your Lord and seek His forgiveness; indeed, He is ever Relenting” (110:3). For that reason ʿĀʾishah (may Allah be pleased with her) said, “He was interpreting the Qur’an.” Agreed upon.