Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrated that I was present when a person was mentioned before the Noble Prophet (peace and blessings be upon him) who had slept through the night until the morning. The Prophet said: This is a person in whose both ears (or he said: ear) the devil has urinated.

Sayyiduna Ali (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) came to him and Sayyidah Fatimah one night and said, "Will you not pray (the Tahajjud) prayer?" I replied, "O Messenger of Allah, our souls are in Allah's control; when He wills, He will awaken us." At this response of ours, the Prophet returned without saying anything, but as he was leaving, I heard him striking his thigh and reciting (this verse from Surah Al-Kahf): "Man is the most quarrelsome of all beings." (Al-Kahf 54)

Sayyiduna Abu Hurairah (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings of Allah be upon him) said: Satan ties three knots at the back of the head of any one of you when he sleeps, and on each knot he breathes the following words: "The night is long, so sleep." Then if one wakes up and remembers Allah, one knot is undone; and when he performs ablution, the second knot is undone; and if he prays (obligatory or voluntary prayer), then the third knot is undone. Thus, in the morning, he becomes energetic and good-natured; otherwise, he becomes lazy and of bad disposition.