Sayyiduna Abu Huraira (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said: "Satan ties knots at the back of the head of any person; when that person sleeps, he ties three knots. On each knot he says, 'The night is long, so keep sleeping.' If that person wakes up and remembers Allah, one knot is undone. If he performs ablution, the second knot is undone. And if he offers prayer, the third knot is also undone. Then, that person becomes energetic and good-natured for the day; otherwise, his temperament is not good and he becomes lazy."