This can be stated in active form. Alternate translation: "I will grieve because many of you have sinned before now and have not repented ... that you have practiced" (See: [[rc://en/ta/man/jit/figs-activepassive]])
Possible meanings are 1) Paul is saying almost the same thing three times for emphasis. Alternate translation: "did not stop commiting the sexual sins that they practiced" or 2) Paul is speaking of three different sins. (See: [[rc://en/ta/man/jit/figs-parallelism]])
The abstract noun impurity can be translated as "things that do not please God." Alternate translation: "of secretly thinking about and desiring things that do not please God" (See: [[rc://en/ta/man/jit/figs-abstractnouns]])
The abstract noun "immorality" can be translated as "immoral deeds." Alternate translation: "of doing sexually immoral deeds" (See: [[rc://en/ta/man/jit/figs-abstractnouns]])
The abstract noun "indulgence" can be translated using a verb phrase. Alternate translation: "of ... doing things that satisfy immoral sexual desire" (See: [[rc://en/ta/man/jit/figs-abstractnouns]])