The Messenger of Allah (ﷺ) forbade that a man should lie placing(and according to Qutaibah's version: "should raise" ) one of his legs over the other. Qutaibah's version adds: When he was lying on his back.
Reference: Sunan Abi Dawud 4865 In-book : Book 43, Hadith 93 English translation : Book 42, Hadith 4847
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