Mark characteristically records details that the other writers do not, and here, he describes the disciples' astonishment. If they had truly believed, nothing should have amazed them. They knew Jesus was the Messiah, but their faith was too weak to believe deeply that He was the powerful God of creation. Mark explains that His multiplying of the loaves and fish just hours earlier should have demonstrated Jesus' true identity to them (Mark 8:18-21), but neither that miracle nor the appearance of Jesus on the water could open their hearts to the reality of His divine nature.

When Jesus had calmed the storm earlier, the disciples had struggled with faith versus fear (Mark 4:40), and now, they struggled with faith versus fear plus hard-heartedness. Their hearts were hardened because their minds were slow to recognize the significance of Christ's miracle. This does not mean that they were conflicted about Jesus, but simply that they were slow to recognize His omnipotence. Once the excitement of the raging sea had settled down, the disciples gained a greater appreciation for the breadth of His power. From this they were able to admire and worship Him, saying, "Truly You are the Son of God" (Matthew 14:33). The disciples' hearts were beginning to soften.

The encouraging lesson of this miracle is that faith is tested by the stormy trials in life, but despite our being tossed about on the waves of a troublesome world, Jesus is always near. We may feel abandoned in times of stress, but Christ has not forgotten us. His intervention may sometimes come suddenly, at other times slowly, yet depending on the will of the Father, there is always the potential for a miraculous solution.