A look at the messianic prophecies in the Old Testament leads us to a seventh important principle of Bible prophecy, stated a couple of times by Jesus: “I have told you now before it happens, so that when it does happen you will believe.” (John 14:29; cf. 13:19) Did Jesus say, “I’ll tell you ahead of time so that you will know the future in advance? I’ll help you make a chart where all the events are lined up so that you can spot your place in history at all times?”
No He did not. He was saying that if you pay careful attention to His words, you will recognize the time of fulfillment when it comes, not before. When the prophesied events occur, you will recognize them and the fulfillment will be clear. It was clear that Jesus was the fulfillment of the messianic prophecies once His life was lived out. But the prophecies did not allow people to predict the exact course of His life in advance. God is not predictable. That means that prophetic fulfillments are best recognized after they occur, not before.

When it comes to unfulfilled prophecy, a little tentativeness is advisable. It was the lack of such tentativeness that led David Koresh to destruction. He thought he knew exactly what God wanted him to do and exactly how to bring about the result that God had in mind. But he was wrong. It is critical that we search the Word to gain an understanding of unfulfilled prophecy. At the same time we need to maintain a sanctified tentativeness about our conclusions. We must leave God the freedom to be God.

The book of Revelation continues the pattern we have seen all the way back to the book of Genesis. When John wrote the book the events described in it were almost entirely future. Yet the basic language of the book of Revelation is the language of John’s past. Revelation is filled with the Old Testament. For example, notice the latter part of Revelation 13:
“And he performed great and miraculous signs, even causing fire to come down from heaven to earth in full view of men. Because of the signs he was given power to do on behalf of the first beast, he deceived the inhabitants of the earth.”
Rev 13:13-14

At the time of the Exodus Pharaoh’s magicians deceived him by using magical arts. In Revelation 13 the magical art is to bring fire down from heaven to earth as Elijah did on Mount Carmel.
He ordered them to set up an image in honor of the beast who was wounded by the sword and yet lived. He was given power to give breath to the image of the first beast, so that it could speak and cause all who refused to worship the image to be killed.
Rev 13:14-15

This is a reminder of Daniel 3 where Nebuchadnezzar set up an image and threatened to kill anyone who refused to bow down and worship it.
He also forced everyone small and great, rich and poor, free and slave, to receive a mark on his right hand or on his forehead, so that no one could buy or sell unless he had the mark, which is the name of the beast or the number of his name.
Rev 13:16-17

This phrase has a history too. In Deuteronomy 6, the Ten Commandments were to be worn on the forehead and the hand. So the mark is in some way a counterfeit of the Ten Commandments. In order to understand the mark of the beast, you have to understand the Old Testament background–the language of the past that John was using.
This calls for wisdom. If anyone has insight, let him calculate the number of the beast, for it is man’s number. His number is 666.
Rev 13:18

The number 666 also has an Old Testament past. The image of Daniel 3 was 60 cubits high, 6 cubits wide and (presumably) 6 cubits deep–666. 666 is also the amount of income Solomon received in the year he turned away from the Lord (1 Kings 10:14). To the Hebrew mind set, the number 666 could be a pointer to the apostasy of Solomon, the son of David.

So when it comes to the book of Revelation we have to understand that God meets people where they are. He gives prophets lessons about the future in the language of the past. The book of Revelation, like other books of the Bible, comes in the language, culture, and historical setting of the inspired writer.