What is the ruling of Islamic law regarding the marriage of a man and a woman who committed adultery before her conversion to Islam, then married without a guardian or mahr, and had a child, despite their repentance and remorse, and is their cohabitation now considered adultery, and what is the ruling on ambiguous divorce pronouncements?

Adultery is a grave crime, but repentance from it is accepted and transforms evil deeds into good ones. An adulterer is not permitted to marry an adulteress except after repentance, and the preponderant opinion is that the marriage is not valid before it. It is preferable to renew the marriage contract if possible, with the presence of the woman's guardian and two witnesses. There is no need to disclose the reason for the renewal. The waiting period (istibra’) has already occurred, and the child is attributed to the father even if the marriage was invalid. It is not a condition to mention the dowry in the contract. A man's statement, "I will divorce you," does not constitute a divorce. One should be wary of obsessive whispers.