It’s interesting to think about the extent to which the Old Testament and New Testament are interwoven and complement one another, and it is important because consistency is necessary for veracity, and because their continuity may tell us something about God’s plans.
The OT narrative that most dramatically parallels/complements the NT is of course Abraham’s near-sacrifice of Isaac. That is, to Christians God’s asking Abraham to sacrifice his son foreshadows God’s own sacrifice of His Son. Are there other such narratives?
Well, the consistent failure of the Jews to follow God’s will might be one. Jesus’ coming as an anointed one is another, as is God’s frequent choice of the underdog. God surprises — never more so than on Resurrection Sunday. The struggle of the Jews against Gentiles who would oppress them begins no later than Exodus, if not before, and continues throughout and the Bible, not excluding the fall of Jerusalem in AD 70 (and perhaps Revelation). Then there is God’s anger at mankind more generally: Again: Adam, Cain, Noah’s contemporaries ……. Revelation.
Then maybe there’s Jews working within a foreign hierarchy and, more broadly, the problem of how godly people are supposed to live in an often ungodly world. You can draw other parallels, too — some more plausible than others, of course. Jesus Himself likened His three days in the tomb to Jonah’s three days in the great fish. Jesus left Egypt, just as Moses did. Then Jesus spent time in the desert, and so did the Hebrews. And so on.
Important numbers in each Testament are 3, 12, and 40. An important place in both is Jerusalem.
Those last are fairly narrow points, of course, but as we’ve already seen there are broader ones, too. And the importance of faith and right behavior is of course consistent, as is the central problem of what to do about sin. Relatedly, there’s people not believing in God and not doing what He wants them to do, despite His commands and warnings, and despite the rewards and punishments attached to them. Book after book, author after author, century after century, in every genre imaginable. Let’s try this, and let’s try this, and now let’s try this to persuade people to follow God.
There’s God’s power and wisdom and benevolence, His permanence and steadfastness and reliability. Kingdoms. Servants. The centrality of people. Human agency; God working with and through people. The importance of the two great commandments, loving God and loving others. Worship, including at the temple or church.
Yes, the two books read as one.
But the NT is certainly more universalist in its message; the OT is much more about the land and one particular tribe in it.
And I don’t want to make too much of all this: A cynic would, after all, simply say that of course there are these parallels — both books are written by Jews (except Luke) steeped in Judaism.
Still, it is always easy to overlook the obvious with the Bible since we are so close to it. And the consistency and development of themes and lessons, both major and minor, is what we would expect to find in His Word, is it not?