Zechariah - Chapter 6
Zechariah looked up and he saw four chariots coming from between two mountains of copper, which represent strong kingdoms. The first chariot was driven by red horses, the second by black horses, the third by white horses and the fourth by spotted and gray horses. (According to Rashi, the red horses represent Babylonia, the black horses are Media, the white are Persia and the spotted are Greece. The Radak says that the black horses are both Persia and Media, the white horses are Greece, the spotted horses are the Arab empires and the gray horses are Rome.) Zechariah asked the angel what these chariots and horses represent; the angel replied that these are the “guardian angels” of the nations that rule over the world. The drivers of the chariots went to G-d, Who gave them permission to rule.
The chariot driven by black horses went to the north, followed by the chariot driven by white horses. The spotted horses went to the south and the gray horses got permission to go out in all different directions. The angel said to Zechariah that the chariots heading north have relieved G-d of his metaphorical pain by destroying Babylonia, who angered Him through their treatment of the Jews. (Why doesn’t it say where the chariot driven by red horses went? Because the red horses represented Babylonia, whose rule was already finished.)
G-d spoke again to Zechariah, saying that he should take people from among the exiles with him to the house of Josiah the son of Zephaniah, who was already living in Jerusalem. They should bring silver and gold with which to make crowns to be placed on the head of Joshua the High Priest. They should tell Joshua that Zerubbabel, the “shoot," will spring up and build the Temple of G-d. (Rashi mentions that there are those who interpret this section as referring to Moshiach, the Messiah, but that in fact it deals with the second Temple period.) Zerubbabel will rule on his throne and the High Priest (Joshua) will be on his throne. The exiles will come from far away to build the Temple and when these things come to pass, everyone will know that it was G-d who told this to Zechariah. And what does it take to make these things come to pass? All you have to do is listen to the word of G-d.