Mark opens with urgency: the beginning of the gospel of Jesus Christ, the Son of God. Through a mashup of prophecies (Exodus 23, Malachi 3, Isaiah 40), he portrays Jesus as Yahweh the Lord himself, the divine warrior king whose way John the Baptist (new Elijah) prepares in the wilderness.
Jesus is baptized; heavens tear open, Spirit descends like a dove, Father declares him beloved Son. Immediately the Spirit drives him into the wilderness where he triumphs over Satan for 40 days.
This launches the new exodus, deliverance from sin and enemies, rushing toward victory on the cross, first confessed by a Roman centurion. Jesus serves and ransoms his people through death and resurrection.