en_tn/col/03/17.md

in word or in deed

"in speaking or in acting"

in the name of the Lord Jesus

Acting in the name of a person here is a metonym for acting to help other people think well of that person. AT: "to honor the Lord Jesus" or "so that others will know you belong to the Lord Jesus and think well of him" or "as if the Lord Jesus himself were doing it" (See: rc://en/ta/man/translate/figs-metonomy)

through him

Possible meanings are 1) because he has done great deeds or 2) because he has made it possible for people to speak to God and so give him thanks. (See: rc://en/ta/man/translate/figs-metaphor)