Mukhtasar Bukhari

Narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings of Allah be upon him) said: "When one of you goes to sleep, Satan ties three knots at the back of his neck. On each knot he breathes the following words: 'The night is long, so keep sleeping.' If he 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 undone, and he rises in the morning energetic and with a cheerful heart. Otherwise, he gets up in the morning sluggish and with a lazy disposition."