These last three chapters are Second Zechariah’s second oracle, describing the completion of God’s plan from the beginning, from before the creation of the world. When God gave God’s people the seven feasts described in Exodus, they were each prophetic of God’s plan of salvation. So far, four of those feasts have been fulfilled in Christ, and chapters 12-14 reflect the fulfillment to come of the last three feasts.
Zechariah saw a man measuring out Jerusalem, yet the more he measured, the bigger Jerusalem seemed to be. In fact it was going to be so big it would have no walls. But wait! Yes, there would be a wall—Almighty God’s glory would surround God’s people with a wall of fire.
And he shall stand and feed his flock in the strength of the Lord, in the majesty of the name of the Lord his God. And they shall live secure, for now he shall be great to the ends of the earth.