en_tn_condensed/zec/03/04.md

those who stood before him

The word "him" refers to the angel. The phrase refers to other angels who were present.

Look

"Pay attention, because what I am about to say is both true and important"

I have caused your iniquity to pass from you

Since Joshua's garments were symbolic of his sinfulness, by removing his garments, the angel removed Joshua's iniquity. Causing iniquity to pass from him is an idiom that means that he had removed Joshua's iniquity. Alternate translation: "I have removed your iniquity from you" (See: rc://en/ta/man/jit/figs-idiom)

dress you in official robes

Here the phrase "official robes" is a metaphor for righteousness. If your language has a word for clothes that people wear only for special occasions, you might want to use it here. (See: rc://en/ta/man/jit/figs-metaphor and rc://en/ta/man/jit/writing-symlanguage)