Narrated Abu Huraira (RA): Allah's Messenger (SAW)said: During your sleep, Satan ties 3 knots at the back of the head of each one of you. On every knot he reads and exhales the following words:" the night is long for you so stay asleep". When the person wakes up and remembers Allah, one knot is undone; and when he performs ablution, the second knot is undone; and when he offers salat, the third knot is undone and he gets up energetic in a good mood and with a good heart in the morning; otherwise he gets up in a bad mood and lazy.

Bukhari