en_tn_lite_do_not_use/1th/04/06.md

no man

Here "man" refers to a man or a woman. "no one" or "no person" (See: rc://en/ta/man/translate/figs-gendernotations)

transgress and wrong

This is a doublet stating the same idea in two ways to reinforce the concept. Alternate translation: "do wrong things" (See: rc://en/ta/man/translate/figs-doublet)

the Lord is an avenger

This can be made explicit. Alternate translation: "the Lord will punish the one who transgressed and will defend the one who was wronged" (See: rc://en/ta/man/translate/figs-explicit)

forewarned you and testified

"told you beforehand and strongly warned against"