Grow As Christ
Jesus wasn't born with infinite knowledge of God, just like you and I, he had to grow into the person God wanted him to be.
The Unity of Jesus’ Person
The unity of Christ is the doctrine that Jesus, although he possesses two distinct and complete natures—he is simultaneously fully God and fully man—is nevertheless one integral person, God the Son incarnate.
The incarnation of the person of the eternal Son as Jesus Christ is one of the great mysteries of the Christian faith. This personal incarnation, in which “the Word became flesh” (John 1:14), is often referred to as the “hypostatic union” (after the Greek word hypostasis, which came to function in the patristic era as a technical term for a “person”).
Jesus’ Divinity
The Bible affirms repeatedly that Christ is fully God, speaking even of “the church of God, which he obtained with his own blood” (Acts 20:28). He is the “image of the invisible God,” the one through whom and for whom “all things were created,” and in whom “all things hold together” (Col 1:15–18). He is “the exact imprint of [God’s] nature” (Heb 1:3), and is addressed by God as God: “Your throne, O God, is forever and ever” (Heb 1:8). Before his incarnation (and during it), he had “equality with God” (Phil 2:6).
This doctrine affirms that Jesus Christ was not merely an extraordinary human being but the incarnate Son of God, who by nature is coequal and coeternal with God the Father.
Jesus’ Humanity
The Bible also affirms repeatedly that Christ is fully man, speaking of “the man Christ Jesus” (1 Tim 2:5) and the Word who “became flesh and dwelt among us” (John 1:14). “Though he was in the form of God … [he] emptied himself, by taking the form of a servant, being born in the likeness of men,” Paul says, “and being found in human form,” he did what only a human can do: “he humbled himself by becoming obedient to the point of death, even death on a cross” (Phil 2:6–8).
And yet there is only one Jesus, one will (Luke 22:42), one Jesus who knew the hearts of men because he was omniscient God and yet a man himself (John 2:24–25), one unified divine person.
The humanity of Christ is his nature as a man, which is, of course, distinct from his divine nature.
Jesus grew in wisdom and knowledge of God.
Jesus understood His purpose in life.
Jesus is twelve years old. If the Mishna is relevant to the first-century Jewish practice, which is likely in this case, then religious instruction would have become more intense for Jesus upon his reaching twelve (m. Niddah 5:6; m. Megilla 4:6; m. ‘Abot 5:12).