en_tn_lite_do_not_use/2co/12/21.md

I might be grieved by many of those who have sinned before now

"I will be grieved because many of them have not given up their old sins"

did not repent of the impurity and sexual immorality and lustful indulgence

Possible meanings are 1) Paul is saying almost the same thing three times for emphasis. AT: "did not stop commiting the sexual sins that they practiced" or 2) Paul is speaking of three different sins. (See: rc://en/ta/man/translate/figs-parallelism)

of the impurity

The abstract noun impurity can be translated as "things that do not please God." AT: "of secretly thinking about and desiring things that do not please God" (See: rc://en/ta/man/translate/figs-abstractnouns)

of the ... sexual immorality

The abstract noun "immorality" can be translated as "immoral deeds." AT: "of doing sexually immoral deeds" (See: rc://en/ta/man/translate/figs-abstractnouns)

of the ... lustful indulgence

The abstract noun "indulgence" can be translated using a verb phrase. AT: "of ... doing things that satisfy immoral sexual desire" (See: rc://en/ta/man/translate/figs-abstractnouns)