Zechariah’s second vision continues a theme that was only briefly noted in the first vision, that is, Yahweh is angry with the nations who treated Judah with “evil” (ra’ah; 1:15).
Zechariah, presumably having lowered his eyes to reflect on the first vision, now looks up to see a second vision. Here he sees “four horns.” The angel identifies the horns as the nations that scattered “Judah, Israel and Jerusalem.” It is important to note that the angel includes “Israel” (the northern kingdom) who was scattered by the Assyrian Empire as well as the Babylonian Empire that scattered Judah (the southern kingdom).
“Horns” are ancient symbols of strength. The represent power as the horns of oxen and bulls terrify whomever they encounter. Presumably Zechariah does not see isolated horns floating in the air or lying on the ground, but he sees horns on powerful, terrifying animals. But, in the end, these “horns” will themselves fear the God who opposes them.
There is no need to press the number “four” and attempt to identify four specific enemies. The number four more likely is symbolic of the four ends of the earth (cf. Zechariah 6:5) or the “four winds of the earth” (cf. Zechariah 2:6), that is, the nations were arrayed against the people of God. The whole earth (“four” representing the ends/winds of the earth) opposed and oppressed God’s people from the time of the Divided Monarchy. The nations were always arrayed against the kingdom of God.
Having asked the angel what the “horns” are, Yahweh shows Zechariah the “four blacksmiths.” They are the agents of destruction; they will defeat the nations that scattered Judah. Just as the nations lifted their horns against Judah, so Yahweh will lift the hammers of his blacksmiths against the nations.
This is no contest. The nations are no match for Yahweh. God is sovereign over the nations. He used them to punish Judah but in their zeal they treated Judah maliciously. Now God judges the nations. This is another example of the great reversal theme that appears throughout Scripture. God reverses the fortunes of Israel; Yahweh liberates them again by defeating the nations. It is another Exodus of sorts as God once delivered Israel from Egypt (one of the nations).
Judah need not fear. God will terrify the nations and they will no longer terrify Judah.
In Second Temple Judaism Israel still lived under the burden of Roman oppression. The nations still had the upper hand. But the hope of Israel was that one would come to strike the nations, rule them and turn the kingdom of this world into the kingdom of the Christ. That is the story of the Apocalypse of Jesus Christ—a vision seen by John and heard by the church. It is still the hope of the people of God.