Does an adulterous wife (who committed illegal sexual for about 2 years and told the complete story to husband and repent to Allah, according to her the last child born was from the adulterer) should be forgiven and given a chance of purifying herself by following Islam whole-heartedly? (If yes how to move in the society? Should the husband's mother be told that the newborn baby in not from the family linage or not since she is much fond of the young boy? Similarly should the father of adulterous wife be told about her sin?) Or should be divorced and left out to darkness? Since she repent she is trying to learn Islam and following it seriously like Hijab, Salah, charity.
Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
The Prophet (Sallallahu Alaihi wa Sallam) said: "The boy is for the owner of the bed and the stone is for the person who commits an illegal sexual intercourse" .(al-Bukhari) The Hadith means that if a person has a wife, she automatically becomes only for him alone a lawful sex-partner. Thus, if she gives birth after passing six months following to their relations, the child belongs to him and he is considered his legitimate father. The rulings of a father and child such as inheritance, etc, put into effect between them regardless the child resembles to his father or not. The lineage of this child would be cancelled only if the husband denies his child and perform "Li'aan" (invoking mutual curses). If he does not perform Li'aan, the child will belong to him since he is the only lawful sex-partner of his wife. This is the opinion of the majority of Muslim scholars; Shafi'ies and Hambalies are among them. This is also one of the opinions of Imam Malik which is adopted by the majority of his followers.
Therefore, we inform our inquiring brother that the child belongs to that husband except if he performs Li'aan. The way of Li'aan is that he has to take four oaths that the child is not for him and in the fifth oath he invokes curse upon himself if the child is for him. If he does so, then the child will not trace back to him.
In this case he cannot perform Li'aan since he does not know that it is not his child.
As for the wife, if she has made sincere repentance, then there is no problem to keep her as wife. But, if she is still practicing the same illegal matters, then he should divorce her. Approving a wife who practices Zina is an act of cuckold; a cuckold is threatened with not entering Paradise as mentioned in a Hadith.
Allah knows best.
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