Verse 15. Lord, have mercy. The word Lord here means Sir, a title of civility, not implying Divinity.

My son. This was an only son, (Luke.) He was possessed with a devil. This calamity was attended with the following symptoms: -- he was lunatic, See Barnes "Mt 4:24"; he was sore vexed, i.e., he suffered greatly, or was greatly afflicted; he fell often suddenly in the manner of persons having epileptic fits; he was dumb, that is, he was dumb except when the fit was coming on him; for Luke says, that when the spirit took him, he cried suddenly out; he foamed and gnashed with his teeth, and wasted away, or became poor and emaciated. It tore him, (Luke,) and scarcely departed from him, or he had only short intervals of reason; for so the passage in Luke, bruising him, hardly departeth from him," should be translated.