Ephesians 3:10-11 His intent was that now, through the church, the manifold wisdom of God should be made known to the rulers and authorities in the heavenly realms, according to his eternal purpose which he accomplished in Christ Jesus our Lord.
We teach the angels in a sense through their observation of the unfolding work of redemption.
Have you read C.S. Lewis’ “Screwtape Letters”? It’s a bit like the plot you describe.
Yes I have.. but thats not anywhere near the scenario I have proposed.. But Screwtape letters is indeed messing about the margins of what I propose.. Basically what I propose is "the Screwtape Letters on Sanctification".. Evil Angels repenting of their deed(s) returning to God/father.. as a prodigal son.. AS HUMANS... With good angels and bad angels as benefactors or malefactors attending the process..
Meaning a human going to hell would be failure twice not once.. Once as an angel and once as a human.. An atheist and others then would be a double moron ugh! failure.. proving twice spiritual dysfunction..