Praise be to Allah.
We have discussed in abundant detail that which supports what you heard about it not being permissible for a Muslim man to marry a woman who is a zaaniyah and that a Muslim woman cannot marry a man who is a zaani unless they both repent and it is established that the woman is not pregnant by waiting for one menstrual cycle before getting married.
What we want to find out from both parties is two important matters, on which the answer will be based.
The first is: did zina take place between them, meaning penetration, not just touching and fulfilling desire, even if ejaculation took place?
The second is: did they repent before the marriage contract was done?
In the light of these two matters we can answer your questions.
If zina took place but they did not repent, then what they heard applies to their situation.
If zina took place between them but they regretted it and repented, then their marriage is valid and there is no need to worry about it.
If zina did not take place, rather the relationship was just touching and no penetration took place, then they cannot be called zaanis, even if ejaculation occurred and those actions constituted major sins, but it cannot be called zina unless there was penetration.
Based on that:
1.If no zina took place, or it took place but they repented, then there is no need to do anything; rather they remain married but they should strive to do a lot of righteous deeds.
2.If zina took place between them and she did not have a period before getting married, then she got married before it was proven that she was not pregnant, this means that the marriage should be annulled.
Shaykh Muhammad ibn Ibraaheem (may Allah have mercy on him) said: It is not permissible to marry a zaaniyah until she repents. If a man wants to marry her, he must wait for one menstrual cycle to establish that she is not pregnant before doing the marriage contract with her. If it turns out that she is pregnant, it is not permissible for him to do the marriage contract with her until after she gives birth.
Al-Fataawa al-Jaami’ah li’l-Mar’ah al-Muslimah, 2/584
Something similar was stated by the scholars of the Standing Committee, al-Fataawa, 18/383, 384
3.If zina took place between them and they did not repent, then they have to annul the marriage and wait one menstrual period to establish that she is not pregnant. He may marry her again, with a new proposal and a new contract and mahr.
In the questions referred to above we said:
The one who committed this sin and did the marriage contract before repenting has to repent to Allah and regret what he did, and resolve not to commit the sin again. Then he may do a new marriage contract. End quote.
4.If you have children from this marriage, then the children should be attributed to their father, because what happened was a dubious marriage contract and he was not aware that the contract was haraam – if he committed zina and did not repent from it. This is different from the case of illegitimate children, in which case the children are not to be attributed to the zaani, rather they should be attributed to their mother.
The scholars of the Standing Committee said:
The correct scholarly view is that the child cannot be attributed to the man unless the intercourse was based on a valid or invalid marriage contract or a dubious marriage contract, or ownership of the slave woman, or dubious ownership of the slave woman, in which case the child is to be attributed to the man, and they may inherit from one another. But in the case of zina, the child is not to be attributed to the zaani; the blood relationship to him is not proven and therefore he cannot inherit from him.
Shaykh ‘Abd al-‘Azeez ibn Baaz, Shaykh ‘Abd al-Razzaaq ‘Afeefi, Shaykh ‘Abd-Allaah ibn Ghadyaan, Shaykh ‘Abd-Allaah ibn Qa’ood
Fataawa al-Lajnah al-Daa’imah, 20/387
The one who studies the question will see that the case mentioned in the question is not quite clear. We do not know whether zina took place or not and we do not know whether repentance took place or not. We do not know whether the woman menstruated before marriage or not. All these factors affect the answer. Hence we have mentioned the answer in all cases. It may be a good idea to discuss this issue with a scholar so that the man can explain exactly what happened and the scholar may give him a detailed answer. We hope that the answer will be helpful to him and there will be no need for further questions or clarification.
With regard to the questioner saying in his question, “But what is certain is that the full consummation came after marriage, i.e., they are not certain that any immoral action took place because there is no evidence to indicate that”, if that is true as he says, that there is no certainty that zina occurred in this case and what it is certain is that full consummation occurred after marriage, then the answer is clear from what we have said, which is that what happened does not affect the validity of the marriage at all and there is no need to annul it or do a new marriage contract, and there is no need to open the door to waswasah concerning their marriage. Rather all they have to do is fear Allah with regard to what remains and strive to do good deeds, in the hope that Allah will accept their repentance and replace their bad deeds with good for He is Oft Forgiving, Most Merciful.
And Allah knows best.