Adam Clarke on Acts 13:44

The next Sabbath day - The good news had spread far and wide, by means of the converted Jews and proselytes.

Almost the whole city - Jews, proselytes, and Gentiles, came together to hear τον λογον του Θεου, this doctrine of God, this Divine teaching, by which so many of their kindred and acquaintance had become so wise and happy. It is not by public discourses merely that people are converted to God; but by the private teaching and godly conduct of those who have received the truth; for, as these are scattered throughout society, they are a leaven in every place.