St. Augustine is credited with this famous interpretation principle: “The New is in the Old concealed and the Old is in the New revealed.” While this is a helpful little ditty that can make us sound profound and pious, what exactly does it mean? More importantly, how does this principle actually work? Exactly how does the New Testament (NT) “reveal” the often confusing and obscure stories of the Old Testament (OT)? And if the NT does in fact “reveal” the true meaning of the OT, why is there still so much disagreement, even among professing Christians, about what the OT is saying?
Augustine’s interpretive principle is really nothing more than a restating of what the Apostle Paul wrote to the Corinthian church in the first century: “Now these things happened to them as an example, and they were written for our instruction, upon whom the end of the ages have come” (1 Cor. 10:11). Similarly, Paul wrote in his epistle to the Romans: “For whatever was written in earlier times was written for our instruction, so that through perseverance and the encouragement of the Scriptures we might have hope” (Rom. 15:4). When Paul wrote these two letters, the only “Scripture” that was available was the OT. Paul is telling his first century audience that the content of the OT is an instructor for the NT Church. He even goes so far as to say that what happened to the historical figures of the OT is an example for first century believers.
Paul affirmed in no uncertain terms that Old Testament stories were relevant for the Corinthians. “These things were written for us,” he insisted. He could hardly have put the matter more forcefully. The stories of tragedy in the wilderness had a message pertinent for Christian readers who lived over a thousand years after the events.
Paul would have no time for individuals or churches that claim that they have a “New Testament” faith. Paul was constantly using examples from the OT to make his points. In fact, not only Paul, but every writer in the NT canon made allusions to and application from, the OT. Since Paul makes no qualifications to his statement, we must come to the conclusion that the entire OT is prophetic of the NT. In order to rightly understand the events and stories contained in the OT, we must interpret them through their fulfillment in the NT. Likewise, we can never fully grasp the significance of the NT without the OT. Which means that we will never understand the complete message of the Bible, without this symbiotic relationship of type in the OT and antitype in the NT.
This is why events in the NT often seem bizarre and arbitrary. An event like the feeding of the 5000 (Mt. 14:13-21) becomes simply a miracle of necessity of Jesus’ part, rather than a fulfillment of the wilderness wandering, with Jesus as the new Moses (Deut. 18:15). An antitype event like the tongues of fire on the day of Pentecost (Acts 2:1-4) remains a mystery without its corresponding type event, the tower of Babel (Gen. 11:1-9). Although literally thousands could be given, these two simple examples provide a framework for a beginning point in biblical interpretation. The type/antitype relationship gives meaning in both directions. In other words, properly understood, the day of Pentecost takes on much more meaning when understood as something of an “undoing” of the confusing of language and the scattering that resulted at Babel. Not only this, the tower of Babel event itself takes on a much deeper meaning, understood through its NT antitype. The tower event from Genesis 11 becomes highly significant and important to the gospel of Christ, not just a weird fact from biblical history.
Hank Hanegraaff often talks about having the “music of the Old Testament” running through your mind as you read the New. This is good advice. Peter Liethart compares biblical interpretation to a “joke,” in the sense of having to know what the author has in mind to “get it.” Jokes often presuppose certain prior understanding of the culture, habits, traditions, beliefs, etc. of a certain group in order to be “funny.” Without this understanding the joke-hearer will not “get it.” The context, the music, and the prior understanding required to “get” the NT is the OT, but modern Christians are largely unaware and ignorant of where certain books in the OT are located, much less what they say. It is this ignorance that leads to so many errors in NT interpretation. The OT introduces us to characters and events that are not fully developed until the NT provides the “rest of the story
 Richard L. Pratt, Jr., He Gave Us Stories: The Bible Student’s Guide to Interpreting Old Testament Narratives (Phillipsburg, NJ: Presbyterian and Reformed,  1993), 15.