Luke
Acts 16:5BSB·traditional attribution

So the churches were strengthened in the faith and grew daily in numbers.

John Calvin Reformed @genevareformer

5. The churches were confirmed. By this we gather, that that which Luke setteth down, or rather touched concerning the decrees of the apostles, was, as it were, put in by the way, being not much appertinent unto the matter. “Accessorium,” accessory. For he commendeth a far other fruit of Paul’s doctrine, when he saith that the churches were confirmed in the faith.

Matthew Henry Presbyterian @wholebiblehenry

Paul was a spiritual father, and as such a one we have him here adopting Timothy, and taking care of the education of many others who had been begotten to Christ by his ministry: and in all he appears to have been a wise and tender father. Here is, I. His taking Timothy into his acquaintance and under his tuition.

Commenting on Acts 16:1-5

John Gill Reformed Baptist @doctorgill

And so were the churches established in the faith,.... Of Christ, both in the grace and doctrine of faith; and that both by the preaching of the Gospel by the apostle and his companions, and by the decrees of the elders delivered by him: and increased in number daily; as well as in gifts and grace.