John 6:19

Rowed five and twenty or thirty furlongs.

About three or three and. half miles. The lake is here about six miles wide. They were about the middle of the lake. It was about three o'clock in the morning. They had toiled nearly through the night, but could make no headway against the wind and waves.

Walking upon the sea.

The words, "walking on the sea," are common to the Evangelists, and can have no other meaning here than that the Lord walked bodily on the surface of the water.--Alford. We may see in it something like an anticipation (not unconnected, it may be, with the intensity of that crisis in his life) of that spiritual body of which we see another manifestation in the transfiguration, and which became normal after the resurrection, reaching its completeness in the wonder of the ascension.-- Ellicott.

They were afraid.

Mark says, They cried out in fright. They regarded the appearance seen through the darkness an apparition and thought it. harbinger of evil.