en_tn/2ki/15/12.md

This was the word of Yahweh

It can be stated clearly that the events described in verse 10 fulfilled the word of Yahweh. Alternate translation: "What happened to Zechariah was according to the word of Yahweh" or "What happened to Zechariah fulfilled the word of Yahweh" (See: rc://en/ta/man/jit/figs-explicit)

Your descendants will sit on the throne of Israel to the fourth generation

Sitting on the throne represents being the king. Alternate translation: "Your descendants will be the kings of Israel for four generations" (See: rc://en/ta/man/jit/figs-metonymy)