John Calvin Commentary Acts 18:3

"and because he was of the same trade, he abode with them, and they wrought, for by their trade they were tentmakers." — Acts 18:3 (ASV)

They were of the same trade. This passage teaches that Paul, before he came to Corinth, was accustomed to work with his hands; and not for pleasure, but so that he might earn his living with his handiwork. It is not known where he first learned his occupation; however, it appears from his own testimony that he worked primarily at Corinth.

And he shows a reason: because the false apostles taught freely, without taking anything, so that they might craftily creep in. Therefore, the holy man would not yield to them in that point, lest he should cause the gospel of Christ to be spoken of evil (1 Corinthians 9:12, 15).

But we may easily gather from this passage that wherever he went (until he was occupied in the continual labor of teaching), he worked at his occupation to earn his living.

When Chrysostom says that Paul was a leatherworker, he does not disagree with Luke at all, because they were accustomed at that time to make tents from skins.