and here it is in the book by Abu Dawud
Book 036, Hadith Number 4986.
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Narated By AbdurRahman ibn AbuLayla : The Companions of the Prophet (pbuh) told us that they were travelling with the Prophet (pbuh). A man of them slept, and one of them went to the rope which he had with him. He took it, by which he was frightened. The Prophet (pbuh) said: It is not lawful for a Muslim that he frightens a Muslim.
wa assalam