During my childhood days, questions ran deep during Advent and Christmas. Raised in a pastor’s home, I learned the biblical facts of Christmas early on. However, the season always raised plenty of questions, most of which centered on “why.” Why did the world need a Savior? Why did His birth take place in such terrible circumstances? Why did that awful King Herod want to kill the Baby Jesus?

While most such Christmas questions were answered during my youth, one remained for years afterward, a question about the purpose for the thirty-plus years Jesus Christ lived on this earth. I had been taught – and correctly so, as Scripture demonstrates – that the main reason the Son of God became a man was so He could die for our sins. I knew that was true.

What escaped me was not so much the purpose for His death, but the purpose for His life. If Jesus came only to die for our sins, I reasoned, why didn’t He just arrive on earth as an adult, teach God’s truth for a few years, and then be crucified? Why all those years of infancy, the childhood days of discovery and growth, and the season of adulthood? If He came only to teach and then die, why did He have to go through all the rest of the daily grind of human living?

Finally, I began to see in Scripture that Christ came not only to die a substitutionary death for sinners, but also to live a substitutionary life. His punishment in dying takes our punishment, because He died in our place, as our substitute. But there’s more. He also lived a perfect life in our place. He fulfilled God’s law on our behalf, to give to us the righteousness our holy God demands.

As the eternal Son of the Father, Jesus already possessed divine righteousness. From eternity past, He was already righteous before the Father. By becoming a man and living in perfect obedience to the law, He earned for us a human righteousness which He could impute to us – that is, credit to our account – when we repent of our sin and trust Him. In His incarnation, He obeyed God’s law not merely for Himself, but also for us. For us sinners, who could not obey God’s law ourselves. For you. For me.

In order to fulfill all righteousness (see Matthew 3:15), Jesus lived in perfect obedience to God throughout the full range of human life and temptation, from birth through adulthood. Thus, Scripture affirms that He “was in all points tempted like as we are, yet without sin” (Hebrews 4:15). Jesus Himself testified that He came to do His Father’s will (John 4:34), and obey the Father’s commandments (John 14:31; John 15:11).

Think of this. Ponder, and be amazed, as you gaze in the awe upon the incarnation. Jesus worked out His ministry of reconciling us to the Father every moment of every day of His life among us for thirty-plus years. Every time He resisted temptation, He did it to honor the Father and to earn for you the righteousness you both lack and need. Every act of compliance to the Father’s will was done with the Father’s glory and your salvation in view. Each step of obedience to the Law of God was taken on your behalf. Every time He chose to trust His Father’s plan rather than pursue the devil’s proffered short-cuts, He was trusting the Father in your place and as your representative.

The grand scope of the incarnate life by which the Son of God came to glorify His Father extends across the decades of His daily life and trial, from a manger near Bethlehem, across a cruel hill at Jerusalem, and to an empty tomb, where even death could not hold Him captive. Never forget how long and how much it took Him to do the work needed to save you.

And it’s not done yet.

Next Friday: “Christ, In Flesh, Forever”

John Roberts is the longtime pastor of First Baptist Church in Sterling.