Paul is not claiming that Jesus was born as we are born. Paul is illustrating a much greater picture of inheritance. It was an ancient rite of the firstborn son to inherit his entire father’s estate. Paul uses this custom to explain that everything belongs to Christ just as a firstborn son would inherit all from his father. In this letter, he clarifies that Christ is the Creator (He is God), everything belongs to Him (everything is within His authority and power) and He is our Savior (He loved us enough to save us from eternal death).
To pay the price of our sins, Jesus died for us. After death, He rose from the grave; never to die again. He is the firstborn from the dead. We that believe in Christ will be resurrected from death to eternal life with Him.
“And although you were formerly alienated and hostile in mind, engaged in evil deeds, yet He has now reconciled you in His fleshly body through death, in order to present you before Him holy and blameless and beyond reproach— if indeed you continue in the faith firmly established and steadfast, and not moved away from the hope of the gospel that you have heard, which was proclaimed in all creation under heaven, and of which I, Paul, was made a minister.” (Colossians 1:21-23, NASB)