What is the meaning of Acts 19:13-20?

13 Then certain of the vagabond Jews, exorcists, took upon them to call over them which had evil spirits the name of the Lord Jesus, saying, We adjure you by Jesus whom Paul preacheth. 14 And there were seven sons of one Sceva, a Jew, and chief of the priests, which did so. 15 And the evil spirit answered and said, Jesus I know, and Paul I know; but who are ye? 16 And the man in whom the evil spirit was leaped on them, and overcame them, and prevailed against them, so that they fled out of that house naked and wounded. 17 And this was known to all the Jews and Greeks also dwelling at Ephesus; and fear fell on them all, and the name of the Lord Jesus was magnified. 18 And many that believed came, and confessed, and shewed their deeds. 19 Many of them also which used curious arts brought their books together, and burned them before all men: and they counted the price of them, and found it fifty thousand pieces of silver. 20 So mightily grew the word of God and prevailed. (Acts 19:13-20 KJV)

William Burkitt’s Commentary

Here observe, 1. That we read not of any in the Old Testament who was bodily possessed with devils and evil spirits: but, in the New Testament, we meet with many both in our Saviour’s time and also in the apostles’, to the intent that the power of Christ might more signally appear in their ejection and casting out.

Observe, 2. How some of the Jewish exorcists, like our jugglers, make it their trade to wander up and down, to get a livelihood by pretending to cure diseases, and cast out devils, seeing what great miracles Paul had done in the name of Jesus, attempted to cast a devil out of a possessed man, by using the same name, though they do not believe in Jesus. But Satan was so far from obeying them, that he made the possessed man fall violently upon them and wound them.

Thence learn, 1. That Satan scorns all human attempts, as weak and impotent, and is conquered only by divine power; Jesus I know; but who are ye?

Learn, 2. That the devil would gladly be God’s ape. The Jewish jugglers would, by all means, imitate the apostles in casting out devils; accordingly, they use the name of Jesus as a charm; but saying the same word with the apostles signified nothing, without exercising the same faith and grace. These exorcists soon found that words without faith would not work to cast out devils and that Christ would not give power to his name when used as a charm.

Learn, 3. That the devil, by God’s permission, has power over those who profane the name of Christ. Satan here was too hard for these conjurers; he rushes upon them and masters them, tears their clothes, wounds their bodies, and, had not God restrained him, had unavoidably destroyed them. Satan’s malice is infinite, but his power is limited and bounded.

Lord! Abate his power, since his malice cannot be abated.

Observe, lastly, How this execution of divine vengeance wonderfully brought about the conviction and conversion of both Jews and Greeks, verse 18. Many believed, and came and confessed their sinful deeds. And as evidence of their detestation of their former faults and follies, they make a bonfire of all their magical books; burning so many of them, as the learned say, the price amounted to eight hundred pounds. Thus these conjurors evidenced themselves to be real converts, by plucking out their right eye, and cutting off their right hand; that is, sacrificing their bosom and best-beloved lust and corruption.

Thence learn, That there is no better evidence of the truth of a person’s conversion, than cheerfully to part with a very profitable and pleasing lust.