In Mark 6:45-52, Jesus knows the need of the disciples during the stormy, night sea. He walks on the water demonstrating that He is God. He reassures the disciples, “Take heart; it is I. Do not be afraid” using the term for the holy name of God, I AM.
In the Bible, the sea represents chaos and evil. Jesus saves us not only from the storms of life but from our sin. (Psalm 130:1 Out of the depths I cry to you, O Lord!”
Immediately he made his disciples get into the boat and go before him to the other side, to Bethsaida, while he dismissed the crowd. And after he had taken leave of them, he went up on the mountain to pray. And when evening came, the boat was out on the sea, and he was alone on the land. And he saw that they were making headway painfully, for the wind was against them. And about the fourth watch of the night he came to them, walking on the sea. He meant to pass by them, but when they saw him walking on the sea they thought it was a ghost, and cried out, for they all saw him and were terrified. But immediately he spoke to them and said, “Take heart; it is I. Do not be afraid.” And he got into the boat with them, and the wind ceased. And they were utterly astounded, for they did not understand about the loaves, but their hearts were hardened.Mark 6:45-52 (ESV)