What is the ruling on the marriage of a man who was afflicted by misgivings of apostasy before his marriage contract, and then contemplated divorce after it, knowing that he did not intend divorce at the time of the contract?

Do not pay attention to the doubt regarding your apostasy before the marriage contract, because the certainty of Islam is not removed by doubt. The phrases you uttered do not constitute a divorce; rather, they are a promise of divorce, which has no legal effect. Turn away from these whispers (of doubt) and seek Allah's help, and occupy your time with what benefits you.