God’s kingdom has broken in to our lives in the person and work of Jesus Christ. This demands a response from us; just as it did in the lives of those who were first on the scene to hear him.
This is how I would summarize the response Jesus calls for in Mark 1:14-20: Hear… Repent… Believe… Follow. We do this once when we come to faith in Jesus, but it is also the ongoing lifestyle of a Christian. We keep hearing the truth. We keep turning away from what is keeping us from Jesus. We keep turning to him in faith; believing that he is our only hope and joy We keep following him in obedience to his call.