Four hose-drawn chariots

Zechariah 6:1-8

I looked up again, and there before me were four chariots coming out from between two mountains—mountains of bronze. The first chariot had red horses, the second black, the third white, and the fourth dappled—all of them powerful. I asked the angel who was speaking to me, “What are these, my lord?”

The angel answered me, “These are the four spirits of heaven, going out from standing in the presence of the Lord of the whole world. The one with the black horses is going toward the north country, the one with the white horses toward the west, and the one with the dappled horses toward the south.

When the powerful horses went out, they were straining to go throughout the earth. And he said, “Go throughout the earth!” So they went throughout the earth.

Then he called to me, “Look, those going toward the north country have given my Spirit rest in the land of the north.”

Zechariah's last vision recalls the first, though that was of riders, not charioteers, and there are puzzling differences of detail. God's patrols compass all 'four corners of the earth. The nations have been judged. Now God's spirit is at rest - in contrast to 1:15 - and there will be peace.

Why?

The four chariots mean the judgment to the world, similar to chapter 1:7  there were four horses.

The Lord is full of mercy, but God is righteousness either, so the sinner should be aware, the sin has to be removed, only God can help us to erase the sins.

The north is Babylon, there is quiet after the chariots get there? For Israelites were captive in Babylon for 70 years, then they will come back to Jerusalem. And the Lord is comfort for their come back.

The four spirits of heaven are the Holy Spirit of the Lord.

How?

The Lord let the prophet saw his plan and His work is working. So we have to work with the Lord either.

How?