Jesus Christ, the firstborn, is therefore head of the Church of the firstborn (Heb. 12:23). All of this is indicated in Paul’s interpretation of the second psalm—
And we declare unto you glad tidings, how that the promise which was made unto the fathers, God hath fulfilled the same unto us their children, in that he hath raised up Jesus again; as it is also written in the second psalm, Thou art my Son, this day have I begotten thee (Acts 13:32-33).
When Christ was begotten from the dead in the resurrection, this was the fulfillment of a promise God made to our fathers. And because Christ entered resurrection life, we may enter His resurrection life. We may be born again.