11 God did extraordinary miracles through Paul, 12 so that when the handkerchiefs or aprons that had touched his skin were brought to the sick, their diseases left them, and the evil spirits came out of them.
13 Then some itinerant Jewish exorcists tried to use the name of the Lord Jesus over those who had evil spirits, saying, "I adjure you by the Jesus whom Paul proclaims." 14 Seven sons of a Jewish high priest named Sceva were doing this. 15 But the evil spirit said to them in reply, "Jesus I know, and Paul I know; but who are you?" 16 Then the man with the evil spirit leaped on them, mastered them all, and so overpowered them that they fled out of the house naked and wounded. 17 When this became known to all residents of Ephesus, both Jews and Greeks, everyone was awestruck; and the name of the Lord Jesus was praised. 18 Also many of those who became believers confessed and disclosed their practices. 19 A number of those who practiced magic collected their books and burned them publicly; when the value of these books was calculated, it was found to come to fifty thousand silver coins. 20 So the word of the Lord grew mightily and prevailed.
Matthew Henry's Commentary on Acts 19:11-20
Commentary on Acts 19:8-12
(Read Acts 19:8-12)
When arguments and persuasions only harden men in unbelief and blasphemy, we must separate ourselves and others from such unholy company. God was pleased to confirm the teaching of these holy men of old, that if their hearers believed them not, they might believe the works.
Commentary on Acts 19:13-20
(Read Acts 19:13-20)
It was common, especially among the Jews, for persons to profess or to try to cast out evil spirits. If we resist the devil by faith in Christ, he will flee from us; but if we think to resist him by the using of Christ's name, or his works, as a spell or charm, Satan will prevail against us. Where there is true sorrow for sin, there will be free confession of sin to God in every prayer and to man whom we have offended, when the case requires it. Surely if the word of God prevailed among us, many lewd, infidel, and wicked books would be burned by their possessors. Will not these Ephesian converts rise up in judgement against professors, who traffic in such works for the sake of gain, or allow themselves to possess them? If we desire to be in earnest in the great work of salvation, every pursuit and enjoyment must be given up which hinders the effect of the gospel upon the mind, or loosens its hold upon the heart.