The Prophets often received visions from the Lord and as a messenger of the Lord was often telling the Word as they received it. Spurgeon calls illustrations windows which let in light drawing attention to great truths. Illustrations can both enlighten and puzzle.
We see Zechariah asking questions in this passage. The Man in the Myrtle trees is a preincarnate appearance of Jesus. He is on a red horse and indeed we will see Him one day on a white horse. This sermon will discuss the significance of this, the importance of the Word and indeed bring us comfort that God is with us and our future is in the Hands of our Almighty God.