Mark 6:49

49 but they saw him walking on the water. "It's a ghost!" they thought, and screamed.

Mark 6:49 Meaning and Commentary

Mark 6:49

But when they saw him walking on the sea
(See Gill on Matthew 14:26);

they supposed it had been a spirit;
a phantom, a spectre, an apparition, a nocturnal demon:

and cried out;
as men affrighted at the sight, and fearing they should be hurt by it, or that it portended some evil to them; (See Gill on Matthew 14:26).

Mark 6:49 In-Context

47 When evening came, the boat was in the middle of the lake, while Jesus was alone on land.
48 He saw that his disciples were straining at the oars, because they were rowing against the wind; so sometime between three and six o'clock in the morning, he came to them, walking on the water. He was going to pass them by,
49 but they saw him walking on the water. "It's a ghost!" they thought, and screamed.
50 They were all terrified when they saw him. Jesus spoke to them at once, "Courage!" he said. "It is I. Don't be afraid!"
51 Then he got into the boat with them, and the wind died down. The disciples were completely amazed,
Scripture taken from the Good News Translation - Second Edition, Copyright 1992 by American Bible Society. Used by Permission.