Verses 45-50 of Chapter 25:

Have you not seen how your Lord lengthens out the shadow? Had He willed, He would have made it constant, but We have made the sun its pilot; then (as the sun climbs up), We roll it up little by little towards Ourselves. And it is Allah Who has ordained the night as a garment for you, and the sleep as a repose of death, and the day as the time of return to life. And it is He, Who drives the winds to be the harbingers of His mercy: then He sends down pure water from the sky so that He may revive the dead land, and quench the thirst of many of His creatures from among beasts and men. We present the same phenomenon over and over again before them so that they may learn a lesson from it; but most people decline to adopt any other attitude than of disbelief and ingratitude.