Thomas needed to see the evidence of Jesus' death to believe that the living Jesus was the same man who died on the cross. In a similar way, Christians live in a world that needs to see the marks of our own death in Christ before they will believe what we preach about Jesus.
Jesus's resurrection proves the reality of the Christian hope for eternal life beyond death. It also demonstrates the divine power available to help Christians live Jesus' way now. Jesus calls Christians to store up treasures in heaven, because that is where our hearts will be. We also hear him saying that our hearts will have immense resources to serve God faithfully and to love others well. We need to be sure that we are investing out devotion, our time, and our money in that eternal hope.
Mark's story about Jesus' resurrection ends with the primary witnesses of his death, burial, and resurrection scared speechless. Yet, when we think about it, Mark's story calls each of us to live fearlessly in the light of Jesus' authority over all things.