RobH_en_tn/jer/21/10.md

I have set my face against this city

This idiom means he "firmly decided." Alternate translation: "I have made up my mind to oppose this city" (See: rc://en/ta/man/translate/figs-idiom)

have set my face against

"am staring angrily at"

this is Yahweh's declaration

Yahweh speaks of himself by name to express the certainty of what he is declaring. See how you translated this in Jeremiah 1:8. Alternate translation: "this is what Yahweh has declared" or "this is what I, Yahweh, have declared" (See: rc://en/ta/man/translate/figs-123person)

It has been given

This can be stated in active form. Alternate translation: "I have given it" (See: rc://en/ta/man/translate/figs-activepassive)

into the hand of the king

Here "hand" represents the power of the king to destroy the city. Alternate translation: "into the power of the king" (See: rc://en/ta/man/translate/figs-metonymy)