Mark 9:18

18 Whenever the spirit brings on a seizure, it throws him to the ground. Then he foams at the mouth, grinds his teeth, and becomes exhausted. I asked your disciples to force the spirit out, but they didn't have the power to do it."

Mark 9:18 Meaning and Commentary

Mark 9:18

And wheresoever he taketh him
The spirit, or devil, whether it be near fire, or water, whatsoever danger, or dangerous place:

he teareth him;
or throws him into it, or dashes him against it; or inwardly racks, tortures, and convulses him:

and he foameth;
at the mouth, like one that is mad:

and gnasheth with his teeth;
through the excessive pain he is in:

and pineth away;
his flesh is withered, dried up, and consumed away. This was the sad deplorable case this child was in, who was his father's only child, and therefore his health and life were very desirable: now he further observes to Christ, saying,

and I spake to thy disciples that they should cast him out, and
they could not.
Christ being absent, he entreated the disciples, who had power against unclean spirits, to cast them out; that they would make use of it, and dispossess this dumb and evil spirit; and who did make trial to cast him out, but were not able to effect it; (See Gill on Matthew 17:16).

Mark 9:18 In-Context

16 Jesus asked the scribes, "What are you arguing about with them?"

17 A man in the crowd answered, "Teacher, I brought you my son. He is possessed by a spirit that won't let him talk.

18 Whenever the spirit brings on a seizure, it throws him to the ground. Then he foams at the mouth, grinds his teeth, and becomes exhausted. I asked your disciples to force the spirit out, but they didn't have the power to do it."

19 Jesus said to them, "You unbelieving generation! How long must I be with you? How long must I put up with you? Bring him to me!"

20 They brought the boy to him. As soon as the spirit saw Jesus, it threw the boy into convulsions. He fell on the ground, rolled around, and foamed at the mouth.