8 And having gone into the synagogue, he was speaking boldly for three months, reasoning and persuading the things concerning the reign of God, 9 and when certain were hardened and were disbelieving, speaking evil of the way before the multitude, having departed from them, he did separate the disciples, every day reasoning in the school of a certain Tyrannus. 10 And this happened for two years so that all those dwelling in Asia did hear the word of the Lord Jesus, both Jews and Greeks, 11 mighty works also—not common—was God working through the hands of Paul, 12 so that even unto the ailing were brought from his body handkerchiefs or aprons, and the sicknesses departed from them; the evil spirits also went forth from them.
Matthew Henry's Commentary on Acts 19:8-12
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.