“‘...“Behold, a man whose name is Branch, for He will branch out from where He is; and He will build the temple of the LORD. Yes, it is He who will build the temple of the LORD, and He who will bear the honor and sit and rule on His throne. Thus, He will be a priest on His throne, and the counsel of peace will be between the offices.”’” (Zechariah 6:12-13)
Following the eight night visions (Zechariah 1:7-6:8), there is a symbolic skit performed to demonstrate what will happen in the eschatological future because of the work of Messiah.
In traditional Jewish interpretation, there are two streams about Messiah—the suffering Messiah and the kingly Messiah. In this text, they are brought together and connected. The kingly Messiah is also the priestly (suffering) Messiah.
https://youtu.be/hS9N3H75RkM