Musnad Abu Ya'la al-Mawsili 159:85

And with his chain of narration, he said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Satan ties three knots at the nape of the neck of one of you. At every knot, he strikes its place, saying: 'You have a long night, so sleep.' If he wakes up and remembers his Lord, one knot is untied. If he performs ablution, one knot is untied. If he prays, one knot is untied. So he wakes up energetic and in good spirits. But if he does not do so, he wakes up with a foul spirit and lazy."