The validity of a marriage when both spouses embrace Islam simultaneously
Chapter on Marriage of Polytheists
Al-Mughni
Book of Marriage
Primary text
When a husband and wife embrace Islam together, their marriage remains valid, regardless of whether consummation has occurred. There is no disagreement among scholars regarding this matter, and Ibn Abd al-Barr reports it as an consensus (ijma). This is because there was no instance of their religions differing. Evidence for this is found in the narration reported by Abu Dawud from Ibn Abbas, where a man embraced Islam during the time of the Prophet, peace be upon him, and his wife later embraced Islam. The Prophet returned her to him, stating she had embraced Islam with him.
Supporting text
It is considered that their utterance of the declaration of faith (Shahada) occurs simultaneously. If one precedes the other, the marriage is nullified. However, there is a potential consideration that the matter is suspended until the end of the session, similar to the ruling on taking possession (qabd). If the ruling of the session is considered as the ruling of the time of the contract, then requiring simultaneous utterance would lead to separation between nearly all Muslim couples before consummation, except for rare exceptions, thereby invalidating the consensus.