Amedee Varin 1860
Today's gospel is a continuation from yesterday where Jesus fed the 5000 with a few fish and loaves. Again Mark is showing us who Jesus is--someone divine who has power over all things.
In feeding the people and multiplying the food Jesus showed power over the physical world. Today he walks on water. Water in Jewish thought, is the source of life. In a desert environment the people really value and appreciate water. The well was a place where people gathered, it was protected and without water the community fell apart through drought or starvation.
What the writers of the gospels were conveying to the people was that Jesus has power over life, that he is the Lord of life, the he can walk across the waters of life.
For the readers of Mark's gospel this would have been a much more powerful message than it is today. Anyone who can walk on water is Lord and master of all life. And let alone could this Jesus walk on water, he could even control the storms of life that went with it. If he had authority over the wind he had authority over all the circumstances of life!