Evil is that for which they have sold their souls-- that they should deny what Allah has revealed, out of envy that Allah should send down of His grace on whomsoever of His servants He pleases; so they have made themselves deserving of wrath upon wrath, and there is a disgraceful punishment for the unbelievers.

And We have made the night and the day two signs, then We have made the sign of the night to pass away and We have made the sign of the day manifest, so that you may seek grace from your Lord, and that you might know the numbering of years and the reckoning; and We have explained everything with distinctness.