لِلَّذينَ يُؤلونَ مِن نِسائِهِم تَرَبُّصُ أَربَعَةِ أَشهُرٍ ۖ فَإِن فاءوا فَإِنَّ اللَّهَ غَفورٌ رَحيمٌ

Those who vow to abstain from their wives have a waiting period of four months. If they reconcile, then indeed, God is Forgiving and Merciful.