Was Christ pre-eternal in His existence like the Father and the Spirit?
Yes. Christ was pre-eternal in His existence just like God the Father and God the Spirit. Colossians 1 presents God the Son as the image of the invisible God, the firstborn of every creature, before all things, and the One by whom all things were created and consist.
Les explains that the Godhead is the invisible spirit out of which God the Son stepped and became visible. Colossians 1 calls God the Son the image of the invisible God and the firstborn of every creature, indicating Christ was pre-eternal in His existence just like God the Father and God the Spirit. By Him all things were created in heaven and earth, visible and invisible, whether thrones, dominions, principalities, and so forth. He is before all things, and by Him all things consist, or are held together. He is the Head of the Body, the Church, the beginning, the firstborn from the dead, referring to His resurrection, that in all things He might have the pre-eminence. It pleased the Father that in Christ all fullness should dwell. The members of the Godhead are not one above the other; they are all co-equal.
Who is the image of the invisible God, the firstborn of every creature: