Grew mightily [lions.] The word kata kratos doth signify that the word increased not a little, (or that these proceedings were not common) as if he should say, that in those increasings appeared rare efficacy, and such as was greater than it used commonly to be. The word grew do I refer unto the number of men, as if he should have said, that the Church was increased, new disciples being gathered together dally, because doctrine is spread abroad. And I interpret that, that the word was confirmed in every one thus, to wit, that they did profit in the obedience of the gospel and in godliness more and more, and that their faith took deeper root.

So mightily grew the word of God - So powerfully. It had such efficacy and power in this wicked city. That power must have been mighty which would thus make them willing not only to cease to practice imposition, but to give up all hopes of future gains, and to destroy their property. On this instructive narrative we may remark:
(1) That religion has power to break the hold of sinners on unjust and dishonest means of living.
(2) that those who have been engaged in an unchristian and dishonorable practice will abandon it when they become Christians.
(3) that their abhorrence of their former course will be, and ought to be, expressed as publicly as was the offence.
(4) that the evil practice will be abandoned at any sacrifice, however great. The question will be, what is right; not what will it cost. Property, in the view of a converted man, is nothing when compared with a good conscience.
(5) this conduct of those who had used curious arts shows us what ought to be done by those who have been engaged in any evil course of life and who are then converted. If what they did when they were converted was right - and who can doubt it? - it settles a great principle on which young converts should act. If a man has been engaged in the slave-trade, he will abandon it, and his duty will not be to sell his ship to one who he knows will continue the traffic. His property should be withdrawn from the business publicly, either by being destroyed, or by being converted to a useful purpose. If a man has been a distiller of ardent spirits as a drink, his duty will be to forsake his evil course. Nor will it be his duty to sell his distillery to one who will continue the business, but to withdraw his property from it publicly, either by destroying it, or converting it to some useful purpose. If a man has been engaged in the traffic in ardent spirits, his duty is not to sell his stock to those who will continue the sale of the poison, but to withdraw it from public use - converting it to some useful purpose, if he can; if not, by destroying it. All that has ever been said by money-loving distillers, or venders of ardent spirits, about the loss which they would sustain by abandoning the business, might have been said by these practitioners of curious arts in Ephesus. And if the excuses of rumselling people are valid, their conduct was folly; and they should either have continued the business of practicing "curious arts" after they were converted, or should have sold their "books" to those who would have continued it. For assuredly it was not worse to practice jugglery and fortune-telling than it is to destroy the bodies and souls of people by the traffic in ardent spirits. And yet, how few people there are in Christian lands who practice on the principle of these honest, but comparatively unenlightened men at Ephesus.

So mightily grew the word of God, and prevailed - The Codex Bezae reads this verse thus: "So mightily grew the word of the Lord, and prevailed; and the faith of God increased and multiplied." It is probable that it was about this time that St. Paul had that conflict which he mentions, 1-Corinthians 15:32 : If I after the manner of men, have fought with wild beasts at Ephesus, etc. See the note there. It means some severe trials not here mentioned, unless we may suppose him to refer to the ferocious insurrection headed by Demetrius, mentioned at the end of this chapter.

So mightily grew the word of God, and prevailed. Over conjuring books, conjurers themselves, yea, even the devils; the power of God going along with it, many were converted; which is meant by the increase of it, and were delivered from the power of darkness, out of the hands of Satan, and translated into the kingdom of Christ. Beza's ancient copy reads, the "faith" of God; and the Syriac version, "faith in God".

So powerfully did the word of God grow - In extent, and prevail - In power and efficacy.