He has made subject to you the Night and the Day; The Sun and the Moon; and the Stars are in subjection by His Command: verily in this are signs for men who are wise.
And the things on this earth which He has multiplied in varying colours (and quantities): verily in this is a Sign for men who celebrate the praises of Allah (in gratitude).[Qur'an 16:12-13]

Narrated Al-Aswad(RA): I asked 'Aisha(RA) "How is the night prayer of the Prophet(PBUH)?" She replied, "He used to sleep early at night, and get up in its last part to pray, and then return to his bed. When the Muadh-dhin pronounced the Adhan, he would get up. If he was in need of a bath he would take it; otherwise he would perform ablution and then go out (for the prayer)."