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

"If we consider either the preaching of the
word, the ministration of the sacraments, or the
public prayers: the Sunday in the eastern churches
had no great prerogative above other days,
especially above the Wednesday and the Friday,
save that the meetings were more solemn, and the
concourse of people greater than at other times, as
is most likely."[15]
And besides these three weekly festivals, there
were also two annual festivals of great sacredness.
These were the Passover and the Pentecost. And it
is worthy of special notice that although the
Sunday festival can be traced no higher in the
church than Justin Martyr, A.D. 140, the Passover
can be traced to a man who claimed to have
received it from the apostles. See chapter thirteen.
Among these festivals, considered simply as
voluntary memorials of the Redeemer, Sunday had
very little pre-eminence. For it is well stated by
Heylyn:--
"Take which you will, either the fathers or the
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