إِنَّمَا النَّسيءُ زِيادَةٌ فِي الكُفرِ ۖ يُضَلُّ بِهِ الَّذينَ كَفَروا يُحِلّونَهُ عامًا وَيُحَرِّمونَهُ عامًا لِيُواطِئوا عِدَّةَ ما حَرَّمَ اللَّهُ فَيُحِلّوا ما حَرَّمَ اللَّهُ ۚ زُيِّنَ لَهُم سوءُ أَعمالِهِم ۗ وَاللَّهُ لا يَهدِي القَومَ الكافِرينَ

Postponement is an increase in disbelief, leading the unbelievers astray. They permit it one year and forbid it another, to align with the number sanctified by God, thus allowing what God has prohibited. Their evil deeds are made appealing to them. God does not guide the disbelieving people.