It is an unlawful thing - This was not explicitly enjoined by Moses, but it seemed to be implied in his institutions, and was, at any rate, the common understanding of the Jews. The design was to keep them a separate people. To do this, Moses forbade alliances by contract, or marriage, with the surrounding nations, which were idolatrous. See Leviticus 18:24-30; Deuteronomy 7:3-12; compare Ezra 9:11-12. This command the Jews perverted, and explained it as referring to contact of all kinds, even to the exercise of friendly offices and commercial transactions. Compare John 4:9.
Of another nation - Greek: another tribe. It refers here to all who were not Jews.
God hath showed me - Compare Acts 15:8-9. He had showed him by the vision, Acts 10:11-12.
Any man common or unclean - See the notes on Acts 10:14. That no man was to be regarded as excluded from the opportunity of salvation, or was to be despised and abhorred. The gospel was to be preached to all; the barrier between Jews and Gentiles was broken down, and all were to be regarded as capable of being saved.