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

But Dionysius does not merely use the term
Lord’s Day. He uses a stronger term than this--"the
Lord's holy day." Even for a long period after
Dionysius, no writer gives to Sunday so sacred a
title as "the Lord's holy day." Yet this is the very
title given to the Sabbath in the Holy Scriptures,
and it is a well-ascertained fact that at this very
time it was extensively observed, especially in
Greece, the country of Dionysius, and that, too, as
an act of obedience to the fourth commandment.[6]
6. The sixth witness in this remarkable series is
Melito of Sardis, A.D. 177. The first four, who
never use the term Lord’s Day, are by direct fraud
made to call Sunday by that name; the fifth, who
speaks of the Lord's holy day, is claimed on the
strength of these frauds to have meant by it
Sunday; while the sixth is not certainly proved to
have spoken of any day! Melito wrote several
books now lost, the titles of which have been
preserved to us by Eusebius.[7] One of these, as
given in the English version of Eusebius, is "On the
Lord’s Day." Of course, first-day writers claim that
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