John Chrysostom

"And when they were come," etc. They came, teaching them that with good reason had they been ordained by the Spirit. They said not what they themselves, but "what God had done with them." It seems to me, that they mean their trials. It was not for nothing that they come here, nor to rest, but providentially guided by the Spirit, to the end that the preaching to the Gentiles might be firmly established. And mark Paul's ardor. …

Homily on Acts 31 ↗

Theophylact of Ohrid

"Having arrived there" (in Antioch) "and having gathered the church, they reported all that God had done with them." The apostle did not say: "what they had done," but "what God had done with them." "God opened the door of faith to the Gentiles." He calls the opening of the door the teaching which the Gentiles received through the apostles.

Commentary on Acts ↗

Dionysius of Alexandria

And in Cephro indeed a considerable church sojourned with us, composed partly of the brethren who followed us from the city, and partly of those who joined us from Egypt. There, too, did God open to us a door for the word. And at first we were persecuted, we were stoned, but after a period some few of the heathen forsook their idols, and turned to God. For by our means the word was then sown among them for the first time, and before that they had never received it. …

Epistle X - Against Bishop Germanus ↗