John Mark
Mark 9:20ESV·traditional attribution

And they brought the boy to him. And when the spirit saw him, immediately it convulsed the boy, and he fell on the ground and rolled about, foaming at the mouth.

John Calvin Reformed @genevareformer

Mark 9:20. And as soon as he saw him. That the devil should rage with more than ordinary cruelty against the man, when he is brought to Christ, ought not to excite surprise; for in proportion as the grace of Christ is seen to be nearer at hand, and acts more powerfully, the fury of Satan is the more highly excited.

Matthew Henry Presbyterian @wholebiblehenry

We have here the story of Christ casting the devil out of a child, somewhat more fully related than it was in Mat 17:14, etc. Observe here, I. Christ's return to his disciples, and the perplexity he found them in. He laid aside his robes of glory, and came to look after his family, and to enquire what was become of them.

Commenting on Mark 9:14-29

John Gill Reformed Baptist @doctorgill

And they brought him unto him,.... The father of the child, and those that were with him, brought the child to Jesus, into his presence, before him: and when he saw him, that is, either when Jesus saw the child, or the child saw Jesus; or the evil spirit in him, and by him which were all at once: straightway the spirit tare him; threw...