Luke begins his genealogy of Jesus by saying, "Jesus, when he began his ministry, was about thirty years of age, being the son (as was supposed) of Joseph..." (Luke 3:23, ESV). So from the beginning we see that a human was not his father! I praise God for Luke's parenthetical "as was supposed" comment! Joseph was a good man who sought to obey God, but he was not Jesus' father. In fact, we were just told the identity of Jesus' Father in the verse before the genealogy: "...and a voice came from heaven, 'You are my beloved Son; with you I am well pleased'" (v22). Even before God audibly claimed to be Jesus' Father, the angel made it clear to Mary. Mary had wondered how she would have a son, since she was a virgin. The angel had answered, "The Holy Spirit will come upon you, and the power of the Most High will overshadow you; therefore the child to be born will be called holy - the Son of God" (Luke 1:35, ESV).
Jesus is divine; that is, he is God! One of his names is Immanuel, meaning "God with us!" (Matthew 1:23). The Bible also teaches that Jesus is God in John 1:, Hebrews 1 (where God calls Jesus "God" and commands the angels to worship him!) and Colossians 1 and 2. Jesus is God.
But Jesus is also Man. Luke's geneaology may have begun with a reference to Jesus' divinity (the son "as was supposed" of Joseph), but the geneaolgy itself points to Jesus' humanity. Jesus is God's Son who was born of woman - through a long line of humans! Luke takes the genealogy all the way back to Adam, the first man. Jesus came through a line of men and women who were far from perfect; real people with real sins. Some of the guys in Luke's list did some pretty horrible things! Matthew, in his genealogy of Christ, even mentions Rahab the prostitute (Matthew 1:5)! The point is, God sent his Son to us and he became one of us! A man with a body - flesh and blood. He took on flesh! But the mysterious and powerful taking on of this flesh (the incarnation) did not give Jesus a marred, sin nature. Jesus was born as a Man with no sin. The Bible teaches that Jesus can identify with us because he is a Man like us, tempted just as we are, yet without sin (Hebrews 2:18; 4:15).
So in Luke's genealogy we see Jesus shining forth as the God-Man. 100% God and 100% Man. Why is this important?
God and man were not on good terms. We had broken God's laws and worshiped other things in his place. So God, in his holiness, was angry with us (Romans 1:18). And we were dead in sin and depravity, hating God and wanting to rule in his place. So God is justly angry with us because of our sin, and we are treacherous rebels who hate God. Who could possibly reconcile these two warring parties? The God-Man!
For there is one God, and there is one mediator between God and men, the man Christ Jesus. 1 Timothy 2:5, ESVBecause he is God, Jesus can represent God to us, bringing God to us. Because he is Man, he can represent us to God, bringing us to God. Because he is the only God-Man, he can reconcile God and man! And that is exactly what he has done! Jesus died for sinful man at the cross; he stood in our place and received our judgment from God. He paid the price with his blood. Rising from the grave, he ascended to the Father's right hand - the place of exaltation and glory! And he has sent his followers to the ends of the earth with the message of reconciliation: Repent of sin and believe on the Lord Jesus Christ! All who come to God through Jesus will be accepted. The God-Man has done it! Glory to the Christ!