Sahih Bukhari
Sahih Bukhari Volume 008, Book 078, Hadith Number 639.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 78. Oaths and Vows
Narated By Anas bin Malik : I heard the Prophet saying, "Perform the bowing and the prostration properly (with peace of mind), for, by Him in Whose Hand my soul is, I see you from behind my back when you bow and when you prostrate."
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