Why Did Jesus Come to Earth as a Baby? 3 Biblical Reasons

By Daniel Szczesniak

For Christians, the best part of the Christmas season is refreshing our hearts and renewing our minds in wonder at the miracle of the incarnation. 

As we annually rehearse this “true meaning of Christmas,” we love to answer the question of why Jesus came to earth.

Here are a few reasons we see in Scripture.

Jesus came:

  • To fulfill the law in our place (Mt 5:17)

  • To call sinners to repentance (Mk 2:17)

  • To serve and to give his life as a ransom for us (Mk 10:45)

  • To save the world (John 3:17)

  • To die (John 12:27)

  • To reveal God’s glory (John 1:14, Hebrews 1:3)

But did you ever consider why Jesus came to earth as a baby?

After all, couldn’t he have simply materialized as a full-grown man?

Adam seems to have been created as a fully adult man, rather than an infant. If Jesus is the “new Adam” (1 Corinthians 15:45), why couldn’t he have been incarnated as a man?

Why Did Jesus Have to Come as a Baby?

Thankfully, the Scriptures give us theologically rich insight into this question. Let’s take a look.

1. to be king

Jesus came to earth as a baby in order to be the rightful heir to David’s throne.

“For to us a child is born, to us a son is given; and the government shall be upon his shoulder, and his name shall be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of his government and of peace there will be no end, on the throne of David and over his kingdom, to establish it and to uphold it with justice and with righteousness from this time forth and forevermore.” - Isaiah 9:6–7

In Isaiah’s prophecy, the promise of the birth of a child has to do with the throne and kingdom of David.

Now, would Jesus be the rightful king of the world if he simply materialized on earth with the body of a 30 year old man? Well, yes, because he is God in the flesh and the second person of the Trinity. Jesus has always had divine rights over all of humanity by virtue of his divinity. 

But would he have been the rightful heir to David’s throne? No. Only a child born in the line of David could fulfill that role.

God had promised David that he would establish a kingdom for “your offspring… who shall come from your body” (2 Samuel 7:12; c.f. Psalm 132:11). This future king, who would be a physical descendant of David, would establish a kingdom that lasts forever.

Jesus had to be born in the line of David to be the rightful heir to the throne of David.

2. to defeat the serpent

Jesus came to earth as a baby in order to be the “offspring of the woman.”

“I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel.” - Genesis 3:15

This is the famous prophecy, right at the beginning of the Bible, where we see the first glimpse of gospel hope.

After Adam and Eve sinned and fell, they (and the serpent) received curses. The curse against the serpent included a promise: The offspring of the woman would give the serpent a death blow, even as the serpent gave the serpent a death blow.

This prophecy was fulfilled at the cross. There, the serpent appeared to win: Jesus, the prophesied son who had finally come to deliver God’s people, was killed on a hill outside of Jerusalem.

Yet we know that his death on the cross was actually the death blow to the serpent, and the means by which we are saved from the power of sin and delivered from the clutches of the enemy.

In order to fulfill that prophecy, Jesus had to be the “offspring” of the woman, and thus had to be born in the normal human way.

3. to be under the law

Jesus came to earth as a baby in order to redeem those who were under the law.

“But when the fullness of time had come, God sent forth his Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons.” - Galatians 4:4-5

In order to fulfill the law in our place, Jesus had to be subject to the law. That means that he had to be fully human, “made like us in every respect” (Hebrews 2:17) as human beings.

“In every respect” includes being in the womb, being born, getting circumcised on the 8th day, experiencing childhood, submitting to and obeying his parents.

And in order to bear the punishment of our sins as our substitute, he had to be fully human—and that means experiencing all the ins and outs and ups and downs of being a human, “tempted as we are, yet without sin” (Hebrews 4:15).

He was both the perfect sacrifice for our sin and the perfect fulfillment of the law’s righteous requirements because he—in all his divine perfection—was incarnated as a human being who was born, lived, and died.

Only as God in the flesh could he bear the fullness of God’s infinite wrath against sin and provide abundant righteousness to impute to us.

Yet only as a human—who, like each of us, first arrived in this world as an infant—could he stand in our place as our substitute, both for wrath and for righteousness.

So, why did Jesus come to earth as a baby?

The Bible tells us that Jesus had to be born as a baby in order to be our king, to be our deliverer, and to be our substitute.

And the wonder of it all is that these are just three of the many, many reasons why we love to think about and celebrate the incarnation.

This devotional was originally given at The Cross Church Youth Christmas Celebration.

Daniel Szczesniak