سُنَّةَ اللَّهِ الَّتي قَد خَلَت مِن قَبلُ ۖ وَلَن تَجِدَ لِسُنَّةِ اللَّهِ تَبديلًا

[This is] the established way of Allah which has occurred before. And never will you find in the way of Allah any change.