Wheresoever it taketh him ( καταλάβη); literally, it seizeth hold of him. This is the Greek word from which comes our "catalepsy," the active form of "epilepsy." It teareth him ( ῥήσσει). This is doubtless the literal meaning.
But there is much evidence to show that it means hero "it striketh or throweth him down." This is the reudering of the Peshito Syriac, and of the Vulgate. The same interpretation is also given by Hesychius as one of the meanings of the word.
St. Luke (Luke 9:39) describes the symptoms thus: "A spirit taketh him, and he suddenly crieth out, and it teareth him ( σπαράσσει αὐτὸν) that he foameth ( μετὰ ἀφροῦ), and it hardly departeth from him, bruising him sorely."
This it will be remembered is the record of one who was himself a physician. He grindeth his teeth, and pineth away ( ξηραίνεται), as though the springs of his life were dried up. The father of the boy is here minutely describing the symptoms when the fit was upon him.
He seems here to express the stiffness and rigidity of the body in the approaches of the malady. And I spake to thy disciples that they should cast it out; and they were not able. They had tried and failed.
This failure is attributed by our Lord (see Matthew 17:20) to their want of faith; or rather to their "little faith ( διὰ τὴν ὀλιγοπιστίαν ὑμῶν)."