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

Christian church simply to repeal, or altogether lay
by, the day or its name, but only to sanctify and
improve both, as they did also the pagan temples
polluted before with idolatrous services, and other
instances wherein those good men were always
tender to work any other change than what was
evidently necessary, and in such things as were
plainly inconsistent with the Christian religion; so
that Sunday being the day on which the Gentiles
solemnly adored that planet, and called it Sunday,
partly from its influence on that day especially, and
partly in respect to its divine body (as they
conceived it), the Christians thought fit to keep the
same day and the same name of it, that they might
not appear causelessly peevish, and by that means
hinder the conversion of the Gentiles, and bring a
greater prejudice than might be otherwise taken
against the gospel."[8]
In the time of Justin Martyr, Sunday was a
weekly festival, widely celebrated by the heathen
in honor of their god, the sun. And so, in presenting
to the heathen emperor of Rome an "Apology" for
his brethren, Justin takes care to tell him thrice that
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