Secret and Hidden Mystery of God

1 Corinthians 2:6-9 “Yet among the mature we do impart wisdom, although it is not a wisdom of this age or of the rulers of this age, who are doomed to pass away. 7 But we speak the wisdom of God in a mystery [G3466: Mystḗrion. Secret, hidden] even the hidden wisdom, which God ordained before the world unto our glory. 8 None of the rulers of this age understood this, for if they had, they would not have crucified the Lord of glory. 9 But, as it is written, “What no eye has seen, nor ear heard, nor the heart of man imagined, what God has prepared for those who love him” 10 these things God has revealed to us through the Spirit.”

We the Ekklesia/Ecclesia would become are (born-again) the sons (daughters) of God and joint heirs with Christ.

True Sons (Daughters) of God.

Yeshua/Jesus – Express Image of the Father. Son
Angels – Created beings. Sons of Elohim/God
Ekklesia/Ecclesia – Become [G1096: to become, i.e., to come into existence, begin to be, receive being to become, i.e., to come to pass, happen. To be made finish] sons of Theos.