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.

And nothing could have hindered Us that We should send signs except that the ancients rejected them; and We gave to Samood the she-camel-- a manifest sign-- but on her account they did injustice, and We do not send signs but to make (men) fear.

So when Our clear signs came to them, they said: This is clear enchantment.