Sahih Bukhari
Sahih Bukhari Volume 001, Book 012, Hadith Number 750.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 12. Charecteristics Of Prayer
Narated By Abu Bakra : I reached the Prophet in the mosque while he was bowing in prayer and I too bowed before joining the row mentioned it to the Prophet and he said to me, "May Allah increase your love for the good. But do not repeat it again (bowing in that way)."