Do past sins and mistakes prevent me from being described as "pure, chaste, virtuous sister, and muhsanah (chaste/protected)"? And is my husband sinful for his ill-will and verbal abuse towards me, and is he considered a slanderer of a chaste woman, or is it not permissible to describe people like me as muhsanah?

A husband's request for his wife to disclose her past is an error, both legally and rationally, and the wife should not comply with it. Disclosing what Allah has concealed regarding the wife's past sins introduces doubt and suspicion into the husband's mind, and may lead him to taunt and insult her, which is forbidden by Islamic law.

Islamic law has prohibited digging into the past and inquiring about matters that might displease the inquirer, as stated in the verse: (O you who have believed, do not ask about things which, if they are shown to you, will distress you) (Quran 5:101).

A wife who has disclosed her past must repent to Allah with sincere repentance, for one who repents from a sin is like one who has no sin. As for the husband, he is not permitted to taunt his wife about her past. If he does so, he is sinful. If he accuses his wife of a past in which no indecency occurred, he is a slanderer. If it did occur and she repented from it, she is also like one who has not sinned, and accusing her after repentance is slander that necessitates the punishment for slander.