Then there was the time that calmed a storm (Mark 5:35-41), and Matthew and John tell of times that the disciples ran into wind and waves--and Jesus walking on the sea toward them. Matthew tells of Peter tried walking to Him, and lost his nerve; and the winds died down. Peter's reaction here was "Beyond doubt you are the Son of God!" (Matt 14:24-33)
At the very end of Jesus' earthly ministry, we find Him again at the Sea of Galilee and the Peter and the others are back in the boats, fishing. And again, they had been fishing all night for nothing. Then a voice from the shore told them to drop the nets on the other side. Again, the nets are totally filled; Peter jumps in and swims to shore, and they are just in time for Jesus to give them bread and fish for breakfast. And Peter gets his last words from Jesus: "Feed my sheep" and "Follow me." Peter's apprenticeship begins and ends with a boat full of fish and the knowledge that even the fish and the sea obey Him.
Jesus' mastery of the sea should not have been a surprise to His followers. They had all had a good yeshiva education (the Maccabees who ruled in the previous century had established schools throughout their territory) and they knew their Scriptures. God had sent a Flood--and boatmaking instructions to Noah. Moses had parted a sea for the Israelites leaving Egypt. Jonah had been on a ship caught in a storm, and realized that he was the target--"He answered, “I am a Hebrew and I worship the Lord, the God of heaven, who made the sea and the dry land.”... Then they took Jonah and threw him overboard, and the raging sea grew calm." (Jonah 1:9-15)
Seas are a good metaphor for the power of God; stronger than we are , incredibly useful in some ways and incredibly dangerous in others. We have some understanding of it, but not nearly as much as we'd like. We can enjoy the beauty and opportunites that it gives, but we also need to respect its power. God gives us the seas to enjoy and use--on His terms, the rules built in from Creation. God Himself is like that--He gives us many good things and opportunites, but there are things He cannot allow. Peter's nets were full of fish--when he followed Jesus' instructions, even in the face of his own discouragement.