History of the Sabbath and First Day of the Week - John N. Andrews

And it is worthy of notice that in a large number of
cases, those Gentiles are termed "devout Greeks,"
"religious proselytes," persons that "worshiped
God," that feared God and that "prayed to God
always." (Acts 10:2, 4, 7, 30-35; 13:43; 14:1;
16:13-15; 17:4, 10-12) These Gentiles, at the time
of their conversion to the gospel, were, as we have
seen, worshipers of God upon the Sabbath with the
Jewish people. When James had proposed the kind
of letter that should be addressed by the apostles to
the Gentile converts, he assigned a reason for its
adoption, the force of which can now be
appreciated: "For Moses," said he, "of old time
hath in EVERY CITY them that preach him, being
read in the synagogue every Sabbath day." The
Sabbatarian character of the apostolic churches is
thus clearly shown.
In a letter addressed to the Corinthians, about
five years after they had received the gospel, Paul
is supposed to contribute a fifth pillar to the firstday
temple. Thus he wrote them:--
"Now concerning the collection for the saints,
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