With the beginning of Jesus' preaching ministry, we have a conclusion, of sorts, to Mark's introduction. He had said, "The beginning of the gospel of Jesus Christ, the Son of God". And now that he's covered Jesus' forerunner, baptism, and temptation, all he has left is the summary statement of Jesus' preaching ministry. It was simple: The time is fulfilled, and the kingdom of God is at hand; repent and believe in the gospel. (4 Minutes/900 Words)