As a young Christian, pastor and author Tim Keller said, "I found the Old Testament to be a confusing and off-putting part of the Bible." But while he was at a study center someone asked the great Bible scholar Alex Motyer a question about the seeming disjointedness between the Old Testament and the New Testament. Keller writes:

I will always remember his answer … [Dr. Motyer] insisted that we were all one people of God. Then he asked us to imagine how the Israelites under Moses would have given their "testimony" to someone who asked for it. They would have said something like this:

We were in a foreign land, in bondage, under the sentence of death. But our mediator—the one who stands between us and God—came to us with the promise of deliverance. We trusted in the promises of God, took shelter under the blood of the lamb, and he led us out. Now we are on the way to the Promised Land. We are not there yet, of course, but we have the law to guide us, and through blood sacrifice we also have his presence in our midst. So he will stay with us until we get to our true country, our everlasting home.
Then Dr. Motyer concluded: "Now think about it. A Christian today could say the same thing, almost word for word."

My young self was thunderstruck. I had held the vague, unexamined impression that in the Old Testament people were saved through obeying a host of detailed laws but that today we were freely forgiven and accepted by faith. This little thought experiment showed me, in a stroke, not only that the Israelites had been saved by grace and that God's salvation had been by costly atonement and grace all along, but also that the pursuit of holiness, pilgrimage, obedience, and deep community should characterize Christians as well.