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

The question of the sinfulness of labor on either
of these days is not here taken into the account; for
the reason assigned is that the slaves may have
leisure to attend public worship. But while these
Constitutions elsewhere forbid labor on the
Sabbath on the authority of the Decalogue, they do
not forbid it upon the first day of the week. Take
the following as an example:--
"O Lord Almighty, thou hast created the world
by Christ, and hast appointed the Sabbath in
memory thereof, because that on that day thou hast
made us rest from our works, for the meditation
upon thy laws."[42]
The Apostolical Constitutions are valuable to
us, not as authority respecting the teaching of the
apostles, but as giving us a knowledge of the views
and practices which prevailed in the third century.
As these Constitutions were extensively regarded
as embodying the doctrine of the apostles, they
furnish conclusive evidence that, at the time when
they were put in writing, the Ten Commandments
were very generally revered as the immutable rule
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