Does divorce occur if the husband did not mention all of his conversations with another woman, knowing that he swore an oath of divorce saying: "You are divorced if I lie to you, or conceal anything"?

You and your husband erred by making divorce contingent on this matter. The majority of scholars hold the view that if a husband makes his wife's divorce contingent on a condition, then she is divorced upon the fulfillment of that condition, whether the husband intended divorce, threat, emphasis, or prohibition. This is the fatwa we follow. However, some scholars, such as Ibn Taymiyyah, are of the opinion that if he did not intend to effect divorce, but rather intended threat, emphasis, or prohibition, then divorce does not occur, but he is liable for an expiation for breaking an oath (kaffarat yamin).

Accordingly, the fatwa we follow is that if your husband lied to you, then divorce has occurred. The reference for determining what constitutes a breach of the oath is the husband's intention and what he meant by what he uttered. If he intended by his oath not to lie or conceal in specific matters, then his oath is confined to them, and he does not breach it if he conceals or lies about other matters.

Al-Nawawi said: "As for when one swears an oath without the judge's request, and uses equivocation (tawriya), the equivocation benefits him, and he does not breach the oath, whether he swore initially without being asked, or someone other than the judge or his deputy asked him to swear in that matter. The intention of the one requesting the oath, if not the judge, is not considered."

Al-Buhuti said: "If his wife makes him swear not to marry another woman, and he swears to her on that, and intends something of what we mentioned, such as intending not to marry a Jewish woman, or a Christian woman, or a blind woman, or an Abyssinian woman, and so on. Or that he will not marry another woman in China, or similar places where he intends to marry, then his intention is valid; because his wording can bear that interpretation."

And assuming divorce has occurred and it does not complete the three divorces, your husband may revoke the divorce (raj'a) before your waiting period (iddah) expires.