The Ruling on Doubt Regarding a Wife and the Lineage of Children

Question:
Honorable Shaykh, a man has doubts about his wife. Is this woman his wife according to the Shari'ah? And does doubt regarding this marriage affect the legitimacy of their children?

Answer:
This is waswas (whispers of doubt). As long as the marriage contract was concluded with its conditions and pillars, she is his wife. This marriage and this nikah (marriage contract) do not end except with certainty, with a divorce that is free from doubt. As long as he has doubts, waswas, and illusions, she is his wife. The default is the continuation of the marriage. Certainty is not removed by doubt, and doubt does not make the lawful forbidden.
Likewise, his children: the child belongs to the bed, as the Prophet (peace and blessings be upon him) said: So as long as she is under his protection, her children are attributed to him. As long as the woman is under his protection, her children are attributed to him, unless he denies them through li'an (mutual oath-swearing in an accusation of adultery), as you have heard. If he denies them through li'an, they are disowned. Yes. Otherwise, they are attributed to him. May it be. His saying (peace and blessings be upon him): . Yes.