The Lord's Day and Commerce

This Sabbath is then kept holy unto the Lord, when men, after a due preparing of their hearts, and ordering of their common affairs beforehand, do not only observe an holy rest, all the day, from their own works, words, and thoughts about their worldly employments, and recreations, but also are taken up the whole time in the public and private exercises of His worship, and in the duties of necessity and mercy.

-Westminster Confession of Faith 21.8

We reject the teaching that the Fourth Commandment is no longer binding under the New Testament.
God promises rich blessings for keeping the Lord's Day holy.

-RP Testimony 21.11-12