Catholic doctrine affirms the eternal pre-existence of the Son of God. The second Person of the Trinity—the Divine Word (Logos)—is co-eternal with the Father, not created in time. The Nicene Creed professes that the Son is 'begotten, not made, consubstantial with the Father; through him all things were made.' The Incarnation is the eternal Son's assumption of human nature in the womb of the Virgin Mary, not the creation of a new divine being.

St. John's prologue (John 1:1–18) and St. Paul's hymns (Philippians 2:6–11; Colossians 1:15–20) are the primary scriptural texts for this doctrine. Catholic theology emphasizes that the eternal, pre-existent Son is the same Person who was born, suffered, and rose—the continuity of divine Person across the Incarnation is essential to the logic of salvation. Only a truly divine and pre-existent Son could redeem humanity.