Since Allah has covered a person’s sins, it is not anyone’s business to seek to lift Allah’s cover of confidentiality. Thus, it is unbecoming of anyone to probe into someone’s sinful past.
Elaborating on this issue, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states that: “Islam teaches that doors of Allah’s mercy are wide open for all sinners, provided they are willing to return to Allah in sincere repentance and respond to Allah’s call. Allah says: “O My Servants who have wronged their souls! Do not despair of Allah’s mercy. For Allah certainly forgives all sins.” (Az-Zumar: 53) In light of the above, we can certainly hope that the Merciful Lord forgives our sins. But one must never take the issue of repentance lightly. It is not simply saying, O Allah, forgive me. Rather, one must first feel deep remorse for the sin, refrain from all associations that led to the same, resolving never to do it again, and finally occupying oneself busy with good deeds.
Islam teaches that we must confess our sins to Allah and Allah alone. By disclosing our sins to humans we are lifting the cover that Allah has placed over them.”
The eminent Muslim scholar, Sheikh Muhammad Al-Hanooti, member of the North American Fiqh Council, adds: “It is not sinful for the girl not to reveal her early actions before making tawbah (repentance) because Allah is the only one who accepts tawbah and who accounts and judges people.
Her concealing of the sins that she committed complies with the guidance of Shari`ah that a Muslim is not in need of revealing what they do of sinful actions. Allah likes evildoings to be unknown and not to be revealed.”
Having said this, however, one must make a definite exception to the above rule. If someone is suffering from contagious diseases (such as being HIV-positive or afflicted with AIDS or other sexually transmitted diseases, etc.), it is incumbent upon him/her to disclose it to the prospective spouse [without adding details of one’s past sex life]. Failure to do so is a most heinous offense, as it may most likely expose the prospective spouse to unnecessary harm, which is not tolerated in Islam.