John Calvin Commentary Acts 16:19

"But when her masters saw that the hope of their gain was gone, they laid hold on Paul and Silas, and dragged them into the marketplace before the rulers," — Acts 16:19 (ASV)

But when her masters. The same devil who recently flattered Paul through the mouth of the maid now drives her masters into a fury, so that they would put him to death. Thus, having changed his approach, he now enacts a tragedy, this devil who could not succeed before with his fair speech and flattery.

And though the fervent zeal with which Paul was provoked to anger raised the whirlwind of persecution, yet he is not therefore to be blamed. Nor did Paul regret at all that he had performed the miracle, to the extent that he wished undone what had been done, because he knew very well by what prompting he had driven the devil out of the maid.

From this we are taught that we must not rashly condemn things that are well done, or what is undertaken at God's command, even if an unfortunate outcome follows. This is because God then tests the constancy of His own, until a more joyful and prosperous end drives away all sorrow.

Regarding the men, Luke expresses the reason why they were so furious with Paul: namely, because their hope of filthy gain was gone. But though they were spurred on solely by covetousness to persecute the Gospel and its ministers, they nevertheless feigned a noble pretext, alleging that it grieved them that public order was being subverted, that their ancient laws were being violated, and that peace was being disturbed.

Thus, though the enemies of Christ behave wickedly and dishonestly, they always invent some justification for their sin. Indeed, even when their wicked desire is plainly apparent, they still act with shameless impudence.

So today, those Papists who are overly zealous for their law have nothing else in their minds besides their own gain and power.

Let them swear and perjure themselves by all their saints and sacrifices that they are compelled only by a godly devotion; yet the matter itself plainly shows that it is the emptiness of their kitchens that makes their zeal so fervent, and that ambition is the fan that fuels it. For they are either hungry dogs, spurred on by greed, or furious lions, breathing out nothing but cruelty.