The disciples became terrified when they saw Jesus walking on the sea because

In the Bible, the disciples became terrified when they saw Jesus walking on the sea because they thought He was a ghost. This story is recounted in the Gospel of Matthew (14:22-33), where it is described that the disciples were in a boat on the sea, and Jesus came to them walking on the water. They were initially terrified, thinking that they were seeing a ghost, but Jesus reassured them and told them not to be afraid. This event is often interpreted as a demonstration of Jesus' power over the natural world and as a lesson about having faith in Him, even in the face of fear and doubt.