I always thought it was the other way around ... The OT can only fully be understood when viewed through the lens of the New Testement. In any event, my best shot at answering this question comes from Ezekiel 36:22-32 NASB
22 “Therefore say to the house of Israel, ‘Thus says the Lord GOD, “It is not for your sake, O house of Israel, that I am about to act, but for My holy name, which you have profaned among the nations where you went. 23 I will vindicate the holiness of My great name which has been profaned among the nations, which you have profaned in their midst. Then the nations will know that I am the LORD,” declares the Lord GOD, “when I prove Myself holy among you in their sight. 24 For I will take you from the nations, gather you from all the lands and bring you into your own land. 25 Then I will sprinkle clean water on you, and you will be clean; I will cleanse you from all your filthiness and from all your idols. 26 Moreover, I will give you a new heart and put a new spirit within you; and I will remove the heart of stone from your flesh and give you a heart of flesh. 27 I will put My Spirit within you and cause you to walk in My statutes, and you will be careful to observe My ordinances. 28 You will live in the land that I gave to your forefathers; so you will be My people, and I will be your God. 29 Moreover, I will save you from all your uncleanness; and I will call for the grain and multiply it, and I will not [fn]bring a famine on you. 30 I will multiply the fruit of the tree and the produce of the field, so that you will not receive again the disgrace of famine among the nations. 31 Then you will remember your evil ways and your deeds that were not good, and you will loathe yourselves in your own sight for your iniquities and your abominations. 32 I am not doing this for your sake,” declares the Lord GOD, “let it be known to you. Be ashamed and confounded for your ways, O house of Israel!”
While this is admittedly a scripture directed towards Israel, it offers an OT typology of what God is doing in the NT through the "born from above".
(v.22-24) It is not done for our sake (although we benefit), but rather for the glory of God's holy name.
(v.25) God does the cleansing, we are the objects covered in filth.
(v.26) God removes a dead heart ... incapable of life and of no value to God or us. God gifts (unmerited) a heart that is alive ... better for us and of value to God (as something other than firewood).
(v.27) God's Spirit (the seal which guarantees our inheritance) dwells in us and empowers us to walk in God's statutes. The dead heart can not and has no desire to walk in the statutes. The living heart desires to walk in God's statutes, but cannot. God's Spirit empowers the new heart to do what it now desires ... to please God!
(v.28) How much more intimate is our NT relationship. We are not merely God's "people", we are God's sons and daughters, the Bride of Jesus Christ.
I could go on, but the point has been made.
Anyway, that's my best guess in answer to your question.