34:9Do they not reflect upon what lies before them and behind them, of the heaven and the earth? If We will, We can make the earth cave in beneath them, or make pieces of the sky fall down on them. In that is a sign for every devout servant.

34:46Say, “I offer you a single advice: devote yourselves to God, in pairs, or individually; and reflect. There is no madness in your friend. He is just a warner to you, before the advent of a severe punishment.”