“BTW, election is a doctrine of both Testaments - see Ephesians 1, for example. And Romans 8.28-30. Predestination and election are Biblical - the question is, how are these realities to be understood ?”
Actually, I disagree with these citations as proof of predestination to eternal glory.
Eph 1:
"3] Blessed be the God and Father of our Lord Jesus Christ, who has blessed us in Christ with every spiritual blessing in the heavenly places, 4] even as he chose US in him before the foundation of the world, that we should be holy and blameless before him. 5] He destined us in love to be his sons through Jesus Christ, according to the purpose of his will, 6] to the praise of his glorious grace which he freely bestowed on us in the Beloved. 7] In him we have redemption through his blood, the forgiveness of our trespasses, according to the riches of his grace 8] which he lavished upon us. 9] For he has made known to us in all wisdom and insight the mystery of his will, according to his purpose which he set forth in Christ 10] as a plan for the fulness of time, to unite all things in him, things in heaven and things on earth. 11] In him, according to the purpose of him who accomplishes all things according to the counsel of his will, 12] we who first hoped in Christ have been destined and appointed to live for the praise of his glory.
13] In him YOU ALSO, who have heard the word of truth, the gospel of your salvation, and have believed in him, were sealed with the promised Holy Spirit…
Who are the “us”, and who the “you also” in this passage?
“Therefore remember that at one time you Gentiles in the flesh …” Eph 2:11
“Us” are the Jews, “you also” the believing Gentiles. The predestination referred to in Eph 1 relates to the temporal blessings accorded the Jews under the old covenant (c.f., Rom 9:4-5 for a similar litany of temporal blessings). It is not predestination to eternal glory