John Calvin Commentary Acts 13:14

"But they, passing through from Perga, came to Antioch of Pisidia; and they went into the synagogue on the sabbath day, and sat down." — Acts 13:14 (ASV)

Entering, on the day of the Sabbaths. He puts the plural number instead of the singular, as often happens in other places of Scripture; for they were accustomed to assemble on the Sabbaths, so that their rest would not be unprofitable and sluggish.

The institution of the Sabbath also had another purpose: that it might be a figure of the spiritual rest when the faithful, being dead to the world and the flesh, abandon their own will and cease from their works. Because we have the truth of this in Christ, while being buried together with Him we put off the old man; therefore, the old figure is past.

But God also had regard for its societal purpose, so that the Jews, being free from all other cares and businesses, might keep their holy assemblies; thus, ceasing from earthly works provided opportunity for their heavenly exercises. So, even today we must use holy days; for we must therefore set aside all other things so that we may more freely serve God.