Expositor's Bible Commentary Commentary Luke 9:39

"and behold, a spirit taketh him, and he suddenly crieth out; and it teareth him that he foameth, and it hardly departeth from him, bruising him sorely." — Luke 9:39 (ASV)

“The next day” may imply that the Transfiguration happened at night. If so, then that great event would have been even more striking. The descent of Jesus and the disciples “from the mountain” meant a descent into the earthly world of illness, evil, and unbelief. A “large crowd” had gathered around a demon-possessed boy. The physical manifestations were similar to those of epilepsy and the boy experienced continual debilitating oppression. While three of the disciples were witnessing the Transfiguration, the others were helpless in the face of demonic power (v.40). Jesus rebuked the spirit and cast it out.