Al-Baqarah · 2:226

226. For those who swear an oath not to have sexual intercourse with their wives, there is a waiting period not longer than four months, starting from the date of the oath. If he abandons the oath and engages in sexual intercourse after having sworn not to, and this happens within the four months period, then Allah forgives them. Allah is merciful and has established compensation as a way out from such an oath.