How do we read the Old Testament? There are two typical tendencies, both mistaken.
The first is simple dismissal of the Old Testament: “Jesus overturned all that.” But this approach doesn’t square with the fact that the Ten Commandments are still valid, that Jesus said he came to fulfill the law not abolish it, and that Jesus is the God of Israel in the flesh.
Another approach is to take everything in the Old Testament as unchanged and unchanging truth. This approach respects the fact that Jesus has a positive relationship with the Old Testament. But it doesn’t respect the fact that Jesus changed some things, too — about the Temple, and the Sabbath, and the kosher laws, for example.
How do we find the path between these two mistakes?
At the beginning of the Sermon on the Mount, Jesus says: “Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill” (Matthew 5:17). A proper approach to the Old Testament depends, in no small part, on understanding what it means for Jesus to “fulfill” the law.
Sometimes we’re tempted to think that fulfillment means simple continuity — a bigger version of the same thing. If you think in terms of a seed, you’ll see the problem with that approach. The fulfillment of a seed isn’t a larger seed. The fulfillment of a seed is a flower or a tree. There’s real continuity there. But the continuity includes development and change, as well.
That’s what we see in Jesus’ relationship with the Old Testament.
• “You have heard that it was said: An eye for an eye and a tooth for a tooth.” There’s the seed. “But I say to you … when someone strikes you on your right cheek, turn the other one to him as well.” That’s the flower — not exactly the same, but a further development of the seed.
• “You have heard that it was said: Love your neighbor and hate your enemy.” The seed planted the idea that your love has to extend beyond yourself. “But I say to you love your enemies and pray for those who persecute you.” That’s the flower — your love has to keep growing, expanding beyond yourself and your neighbor until it encompasses your enemies.
Some parts of the Old Testament — like the Ten Commandments — have a validity that endures forever. Some parts — like Abraham being asked to sacrifice Isaac — only make sense as a foreshadowing of Jesus. And some parts were appropriate to a particular stage of Israel’s development as the people of God, but no longer apply after the coming of Jesus.
When we come to know all of salvation history, we come to know the seed by knowing the flower. This helps us to understand what it means for Jesus to fulfill the law and the prophets. And it helps us find the right approach to the Old Testament.