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

Clement has used, and the very language also in
which he has expressed them.[29] Philo was a
mystical teacher to whom Clement looked up as to
a master. A statement which we find in Philo, in
immediate connection with several curious ideas,
which Clement quotes from him, gives, beyond all
doubt, the key to Clement's suggestion that
possibly the eighth day should be called the
seventh, and the seventh day called the sixth. Philo
said that, according to God's purpose, the first day
of time was not to be numbered with the other days
of the creation week. Thus he says:--
"And he allotted each of the six days to one of
the portions of the whole, TAKING OUT THE
FIRST DAY which he does not even call the first
day, that it may not be numbered with the others,
but entitling it ONE, he names it rightly, perceiving
in it, and ascribing to it, the nature and appellation
of the limit."[30]
This would simply change the numbering of the
days, as counted by Philo, and afterward partially
adopted by Clement, and make the Sabbath, not the
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