John Calvin Commentary Acts 19:9

"But when some were hardened and disobedient, speaking evil of the Way before the multitude, he departed from them, and separated the disciples, reasoning daily in the school of Tyrannus." — Acts 19:9 (ASV)

Seeing their hearts were hardened. We do not read that Paul was heard as patiently and favorably by the Jews at any place as he was at Ephesus during his first coming. For while others, raising tumults, drove him away, these requested him to stay longer. Now, after he had endeavored for three months to establish the kingdom of God among them, the ungodliness and stubbornness of many showed itself. For Luke says that they were hardened. Surely, such is the power of the heavenly doctrine that it either makes the reprobate mad or else more obstinate—and that not by nature, but accidentally, as they say, because when they are urged by the truth, their secret poison breaks out.

Luke adds that they spoke evil of the Way before the people. For those who despise the gospel also vehemently oppose that before others which they themselves will not embrace. And they do this for no other reason than because they desire (if it is possible) to have all people as partners in their impiety.

It is well known that every ordinance is understood by this word Way; but here it refers to the gospel of Christ.

Now, Luke says that Paul departed from them and separated the brethren. By this example, we are taught that when we experience desperate and incurable stubbornness, we must no longer labor in vain. Therefore, Paul admonishes Titus to avoid a man who is a heretic after one or two admonitions (Titus 3:10).

For the word of God is unjustly blasphemed if it is cast to dogs and swine. Also, we must care for the weak, lest through wicked backbiting and the slandering of sound doctrine, their godliness be subverted.

Therefore, Paul separated the disciples, first, lest the goats should with their stench infect the flock of sheep, and secondly, so that the pure worshippers of God might make their profession freely.

Disputing daily. This passage shows how continual Paul’s diligence was in teaching, and that those who are immediately weary of learning are too crude and particular. For we see how few come daily who are ready and fit to hear.

And though he had a particular care for the household flock which he had gathered as into a sheepfold, yet he does not allow strangers to be destitute of his labor; but continuing the course of his disputation, he tries to find any who are fit to be taught.

He calls it the school of Tyrannus, not meaning a man who had obtained the government of Asia (for the Romans ruled throughout all Asia), but it is to be thought that the school was built at the expense of one Tyrannus and given to the city. Therefore, the faithful used a public place, which bore the name of the builder, where they had their assemblies.