Sahih Al Bukhari – Book of Beginning Of Creation
Volumn 004, Book 054, Hadith Number 495.
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Narated By Abu Said Al-Khudri : The Prophet said, "If while you are praying, somebody intends to pass in front of you, prevent him; and should he insist, prevent him again; and if he insists again, fight with him (i.e. prevent him violently e.g. pushing him violently), because such a person is (like) a devil."