Sayyiduna Jabir (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said to me: Whenever any man or woman (goes to sleep), a knot is tied on their head at the time of sleeping. If they wake up and remember Allah Almighty, the knot is untied. If they get up, perform ablution, and offer prayer, then all the knots are untied.