In short, this matter is too weighty in the hearts of believers to require extensive evidence, for faith and the Quran forbid such things. Nevertheless, many Muslim scholars among the Successors and later generations—whose learning, piety, and high standing are beyond doubt—have permitted such things on the basis of an interpretation they adopted. It has therefore been necessary to discuss the matter at length.

There are many comparable cases: an opinion may be exceedingly weak, yet its weakness remains unclear to many people of learning and faith, including eminent figures. For when Muslims disagree, Allah has made reference to the Book and the Sunnah the only safeguard against error. Everyone’s statements may be accepted or rejected, except those of the Messenger of Allah, peace and blessings be upon him, who does not speak from his own desire.

If it is asked: What, then, of His statement:

“A fornicator marries none but a woman who fornicates or a polytheist woman”?

The answer is: This indicates that a fornicator who has not repented may not marry a chaste woman, as stated in one of the two opinions reported from Ahmad. For if he continues to have intercourse with this woman, that woman, and another, as before, his intercourse with this wife is of the same kind as his intercourse with the other women who fornicate. Al-Shaʿbī said: “Whoever marries his daughter to an immoral man has severed his bond of kinship with her.”

Moreover, if he commits adultery with other men’s wives, this is something that prompts his own wife to make herself available to another man, as frequently happens. I have never seen a man who has illicit intercourse with other men’s wives or with males without thereby driving his own wife to commit adultery with someone else, in retaliation and to spite him.

Furthermore, if illicit intercourse is his habitual practice, he finds satisfaction with prostitutes and fails to satisfy his wife sufficiently to keep her chaste, leaving her in need of illicit intercourse.