Ephesians 3:1-6 For this reason I, Paul, a prisoner for Christ Jesus on behalf of you Gentiles— assuming that you have heard of the stewardship of God’s grace that was given to me for you, how the mystery was made known to me by revelation, as I have written briefly. When you read this, you can perceive my insight into the mystery of Christ, which was not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit. This mystery is that the Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel.
There’s so much about God that we’ll never be able to understand in this life and much of that won’t even be revealed to us until such a time as we can better accept it. The Father does, however, from time to time, choose to reveal mysteries about himself.
When Paul wrote his letter to the church in Ephesus, he wrote to a people that had long heard of the coming of the Christ, of the Messiah. The Jews in that time were quite aware of the prophesies about the Sent One, but some of them missed Him when He came in the flesh. The invisible God dwelled in a physical body (Colossians 1:15), revealing all of His nature (Hebrews 1:3), but He went unnoticed by many.
Then God chose to do something unexpected. He revealed himself to those outside the “chosen people.” He made it possible for the so-called Gentiles to join into His family. For most of us today, this has personal significance. If you are not of Jewish lineage and you have put your faith in Jesus Christ and received His salvation and adoption as one of God’s own children, this means everything.
We’ve been brought in on a promise made to a people long ago. We’re now coheirs under that promise, able to receive all that is due to God’s people, to His children. We are now His family.