From Philippians, Colossians, Philemon, by Dennis Hamm SJ, commenting on Colossians 1:12-20.
Paul begins his marvelous hymn by describing the preeminence of God’s beloved Son as image of God and as firstborn of all creation. Describing Christ as the image (Greek eikōn, from which our word “icon” is derived) of the invisible God, he turns the focus to the incarnate Son, Jesus, since only the enfleshed Son is visible. This means that to look upon Jesus of Nazareth is to see the face of the eternal, invisible God. The word “image” echoes Gen 1:26–27 (“Let us make man in our image”) and prepares the way for understanding Christ as the new Adam (see Col 3:10).
When he calls the Son the firstborn of all creation, he uses the rich biblical notion of a firstborn son as preeminent in a family in two ways: (1) the firstborn is chronologically first to be born to his parents; (2) he has greater privilege and honor (e.g., in measure of inheritance) than other siblings.
Paul proceeds to apply this concept to the eternal Son in two different ways, each of which uses both senses of “firstborn.” First, the Son is firstborn in the sense that he is, with the Father, the source and sustainer of all created things (vv. 16–17). As firstborn, he is heir to the entire universe. Second, he is chronologically the first to rise from the dead; and as risen Lord he is the foundation and capstone of the new creation, the Church (vv. 18–20). In both the original creation and the new creation, Christ is prior in time and supreme in honor.
In verse 16 Paul speaks of the eternal Son before his incarnation. A vast world of things was created over the course of the enormous era we call BC (some 13.7 billion years, astronomers tell us). The Son was not himself created. He is “firstborn” of all creation because of his status as agent of all creation from the beginning—as we say in the Nicene Creed, “begotten, not made.”