John Chrysostom : See again Paul judaizing. "Where it was thought," it says, both from the time and from the place, "that prayer would be." Out of the city, by a river side: for it is not to be supposed that they prayed only where there was a synagogue; they also prayed out of synagogue, but then for this purpose they set apart, as it were, a certain place, because as Jews they were more corporeal - and, "on the sabbath-day," when it was likely that a multitude would come together. "And we sat down, and spake to the women which resorted thither." Mark again the freedom from all pride. "Out of the city." The place was convenient for hearing the word, aloof from troubles and dangers. "On the sabbath." As there was no work going on, they were more attentive to what was spoken. — Homily on Acts 35 Oecumenius : Not only where the synagogue was, but also outside they prayed, as if separating some particular place for this purpose, namely the Jews being excessively given to bodily things. Or rather, perhaps there was no synagogue there because of the thin population; beside the river outside the city the supposedly pious used to meet secretly. [CHRYSOSTOM] — Commentary on Acts