Then I looked up again and saw four chariots coming from between two bronze mountains.
The first chariot was pulled by red horses, the second by black horses,
the third by white horses, and the fourth by dappled-gray horses.
"And what are these, my lord?" I asked the angel who was talking with me.
He replied, "These are the four spirits of heaven who stand before the Lord of all the earth. They are going out to do his work.
References for Zechariah 6:5
The chariot with black horses is going north, the chariot with white horses is going west, and the chariot with dappled-gray horses is going south."
References for Zechariah 6:6
The powerful horses were eager to be off, to patrol back and forth across the earth. And the LORD said, "Go and patrol the earth!" So they left at once on their patrol.
Then the LORD summoned me and said, "Those who went north have vented the anger of my Spirit there."
References for Zechariah 6:8