Luke tells us twice that Jesus grew. As a child, He “grew and became strong in spirit, filled with wisdom, and the grace of God was upon Him” (Luke 2:40). And again, a few verses later, He “increased in wisdom and stature, and in favor with God and men” (Luke 2:52).

These passages raise a profound question: if Jesus is God, how can He grow in wisdom? Is not omniscience, the state of being all-knowing, an inherent characteristic of God? So how can the One who knows everything increase in anything?

Here is the heart of the answer. Jesus is one person in two natures — fully God and fully man. As God, the Son knows all things and does not change. As man, He had a real human mind that began as an infant's and grew, as every human mind grows. Both are true of the same person, because that person is both God and man. So when Luke writes that Jesus “increased in wisdom,” he is telling us the truth about the Son of God — according to His humanity. The eternal Son did not grow wiser in His deity. He grew in wisdom in the human nature He had taken to Himself.

There is no contradiction here, because the two natures were not in competition. Even as His human mind was learning its first words, the same Son, as God, was upholding the universe and knowing all things (Colossians 1:17). The infinite was not shrunk to fit the manger. The eternal Son took up a true human life and lived it from the inside — while never, for a moment, ceasing to be all that God is.

Also unlike Adam, who was created as a grown man, Jesus was conceived and born and grew like any other child — yet without sin, and without the inherited guilt of Adam (Luke 1:35; Westminster Confession 8.2). He learned to speak, to read the Scriptures, to reason. By the age of twelve His understanding already astonished the teachers in the temple:

Luke 2:47 (NKJV)

And all who heard Him were astonished at His understanding and answers.

Scripture also shows us how His human life was sustained — by the Holy Spirit. The child who grew in wisdom did so as the Spirit rested upon Him, exactly as Isaiah had foretold:

Isaiah 11:2 (NKJV)

The Spirit of the LORD shall rest upon Him, the Spirit of wisdom and understanding, the Spirit of counsel and might, the Spirit of knowledge and of the fear of the LORD.

The Son of God, living a genuinely human life, drew His human wisdom and strength from the Spirit — as we are meant to.

This is also what Paul means by the famous “emptying.” Writing of Christ's humility, he says the Son “made Himself of no reputation” — in Greek, ekénōsen, “He emptied Himself,” from which we get the word kenosis:

Philippians 2:5–8 (NKJV)

Let this mind be in you which was also in Christ Jesus, who, being in the form of God, did not consider it robbery to be equal with God, but made Himself of no reputation, taking the form of a bondservant, and coming in the likeness of men. And being found in appearance as a man, He humbled Himself and became obedient to the point of death, even the death of the cross.

The emptying is the taking. Christ emptied Himself not by subtraction — pouring out His deity or laying down His divine attributes — but by addition: “taking the form of a bondservant.” He veiled His glory beneath a real human life and submitted Himself to the Father's will; He did not vacate His divinity to do it.

This is why the Reformed tradition has always rejected the kenotic theology of certain writers, who read Philippians 2 to mean that Christ surrendered some of His divine attributes and became, for a time, less than God. If that were true, He would not have been God on earth — and the Saviour we needed must be fully God, or His death could not save.

The gospels record moments when His divine knowledge broke plainly through the veil: He knew men's thoughts (Matthew 9:4), needed no one to tell Him what was in a person (John 2:24–25), knew a stranger's whole history and a friend's death from far away (John 4:17–18; 11:11–14). And there were things He asked about, and learned, and grew into, as a man.

This even answers the verse where Jesus says no one knows the hour of the end times — not even the Son, but only the Father (Mark 13:32). How can the omniscient Son not know? In the very same way He could grow in wisdom at all: according to His human nature. As God, He knew the day. As man — in the knowledge He lived by, day to day, in submission to the Father — it had not been given Him.

The Son of God did not merely appear to be human. He took a true human nature and grew up inside it — learning to speak, to reason, to obey — so that there is no part of our weakness He has not passed through Himself. That is why He is the High Priest we needed: not one who watches our frailty from a distance, but one who “can sympathize with our weaknesses,” having been “in all points tempted as we are, yet without sin” (Hebrews 4:15). The God who knows all things learned, as a child, what it is to be us.

In conclusion, Jesus' growth in wisdom as described in Luke is a profound illustration of His complete humanity. While He never ceased to be fully divine, He embraced the human experience, including learning and growing in wisdom. This aspect of Jesus' life demonstrates His humility and identification with humanity, but also establishes Him as a Great High Priest, uniquely able to sympathize with our weaknesses (Hebrews 4:14-16).