When J. Alec Motyer was questioned about the relationship of Old Testament Israel to the church, after saying something about the discontinuities, he insisted that we are all one people of God. Then he asked us to imagine how the Israelites under Moses would have given their ‘testimony’ to someone who had 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 lead 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.’
Source: A Christian's Pocket Guide to Loving The Old Testament: One Book, One God, One Story, forward by Tim Keller, p x. Dr Motyer passed into glory this August. A tribute here.