Often times in literature, and especially the Bible, there are certain themes that run consistently throughout the text, pointing to a specific culmination. The Bible is no exception, and all the themes point to Jesus – either an aspect of His work or what it accomplished. D. A. Carson calls these themes, “trajectories”; I have often explained them in terms of snowballs.
In the beginning of the text there will be a theme like creation, marriage, sacrifice, or something else. As the story of the Bible unfolds, the same theme will crop up in various places, and pick up a little more meaning. Similar to how a snowball gains size as it rolls down a hill, so does the theme gain meaning as it rolls through the text. In the end, we see the final culmination in Jesus Christ.
To give an example of these themes, I am going to include some notes I made for a group at my church. These notes fit into a larger context, but I believe they will be helpful in order to gain the general idea I am trying to convey. After walking through the exodus account in detail (you can read the rest of the notes here, or just read the through the story in Exodus chapters 1-14), these are just a few of the themes, trajectories, or snowballs that I picked up on:
Mediation
One significant role we see Moses filling is that of the mediator between Yahweh and His people. Yahweh both speaks through Moses, and uses Moses to perform miracles (Ex. 4:12). When Jesus came as fully God and fully man, He became the Ultimate Mediator; it is through the Mediation of Christ that the people of God are saved (cf. Deut. 18:15-18, John 3:12-15, Heb. 3:1-5).
Firstborn
In the Exodus account, Yahweh calls Israel His firstborn Son. In the gospel of Matthew, he cites Hosea 11:1 (a text specifically referring to the Exodus account), and says that “out of Egypt I called my son” is a reference to Jesus Himself. Paul makes the point clear in Col. 1:15 that Christ is the “firstborn over all creation.” Jesus is the True Firstborn Son of the Father.
Substitution
As the theme builds from Abraham and Isaac (Gen. 22), through the Passover sacrifice, we see the substitution of a lamb for the firstborn throughout the Old Testament. It is in this backdrop that John the Baptizer exclaims, “Behold, the Lamb of God, who takes away the sins of the world!”(Jn. 1:29). The people of God are saved in the same way that the Israelites were; because of the blood of the lamb – yet we know now that the True Lamb of God has come, and we are saved only by His blood.
New Creation
As the separation of the waters and the movement of the Holy Spirit (“ruach”) signified God’s first act of creation (cf. Gen. 1:1-4), and the strong east “ruach” dried the waters after the flood (cf. Gen. 8:1), so now we see God separating the waters of the Sea with His “ruach,” as Yahweh is now creating His chosen nation (cf. Ex. 14:21). When Jesus came to save His Church, He sends His Spirit into them, making us “new creatures” in Him (cf. Eze. 36:25-26, John 20:22, 2 Cor. 5:17).
And many more…
I really have not done these passages any sort of justice, but I just wanted you to be able to get the general feel for how to see these Biblical themes, and how they point to Christ. There are literally dozens of themes like this woven throughout the text. A few resources that are very helpful in finding them are:
Clowney, Edmund. The Unfolding Mystery: Discovering Christ in the Old Testament.
Beale, G. K., and D. A. Carson. Commentary on the New Testament Use of the Old Testament.
