Sayyiduna Jabir bin Abdullah (may Allah be pleased with both of them) narrates: The Prophet Muhammad (peace and blessings be upon him) used to say: "Close the mouth of the water-skin when you go to sleep at night, and cover food and drink, because the devil comes; if he finds a door not closed, he enters, and if he finds the mouth of a water-skin not closed, he drinks from it. But if he finds the door closed, or the mouth of the water-skin closed, he cannot open the closed mouth of the water-skin nor the closed door. And if a person does not find anything to cover his vessel in which his drink is, then he should place even a piece of wood over it."