The message of Yahweh to Zechariah was very simple. Return to Yahweh! Yahweh had been angry at their ancestors. All they had to do was to return to him and he would return to them. The Yahweh of hosts, via Zechariah, had a clear message of conversion or reconversion.
Yahweh gave them one last chance to convert to him. He wanted this shameless country to gather together to seek him. If they did not, they would be driven away like useless chaff. If they did not, the anger of Yahweh would come upon them on the day of his wrath. The humble or the poor of the land should seek Yahweh. All they had to do was to follow his commandments. They had to seek righteousness and humility. Then perhaps, on the day of Yahweh’s wrath, they would be hidden or stored away from his anger. There still was a chance for these righteous humble poor people.