The coming of Jesus to this earth as the Son of God fulfilled several functions at the same time. In the first place, as the Divine Son of God, Jesus came to reveal the Father to us. Through His actions and words, Jesus showed us what the Father really is like and why we could trust and obey Him.
Jesus also came as the promised Son of David, Abraham, and Adam, through whom God had promised He would defeat the enemy and rule the world.
Thus, Jesus came to take the place of Adam at the head of humanity and fulfill the original purpose God had for them (Genesis 1:26-28, Psalm 8:3-8). Jesus came to be the righteous ruler God always wanted this world to have.
“The word that was spoken to Jesus at the Jordan, ‘This is My beloved Son, in whom I am well pleased,’ embraces humanity. God spoke to Jesus as our representative. With all our sins and weaknesses, we are not cast aside as worthless. ‘He hath made us accepted in the Beloved.’ Ephesians 1:6. The glory that rested upon Christ is a pledge of the love of God for us. … The light which fell from the open portals upon the head of our Saviour will fall upon us as we pray for help to resist temptation. The voice which spoke to Jesus says to every believing soul, This is My beloved child, in whom I am well pleased” — Ellen G. White, The Desire of Ages, p. 113.