Sahih Bukhari Volume 1, Book 12, Hadith Number 781

Narated By ‘Aisha : The Prophet used to say frequently in his bowing and prostrations “Subhanaka-Allahumma Rabbana Wabihamdika, Allahumma Ighfir-li” (I honor Allah from all what (unsuitable things) is ascribed to Him, O Allah! Our Lord! All praises are for You. O Allah! Forgive me). In this way he was acting on what was explained to him in the Holy Qur’an.