By turning from evil and trusting God alone, Jesus proved to be the obedient Son of God come to suffer for those He would save.
God prepared the way for sinners to enter His Kingdom: by calling them to repent and by accepting the work His Son would do on their behalf.
This new King came to shepherd His people in humility, He is the Son of God's deliverance, and is the savior who brings restored hope.
Joseph's faith in Jesus' miraculous conception assured Jesus' rightful inheritance of David's throne.
God's promise to make a people and bless them with a king are fulfilled in the birth of Jesus.