That Origen, after relating many fables concerning the eternity of the universe, adds this also: 'Neither, then, did man—as some say—not existing before, then first fashioned, come into the world from Adam; nor again did the world begin to be created six days before the generation of Adam.'
But if anyone should kindly desire to dispute against these things, let him first state whether, according to the book of Moses, the time from the world's generation will not be easily numbered by those who so understand it, when the prophetic voice cries even here: 'From everlasting to everlasting Thou art; for a thousand years in Thine eyes are as the day of yesterday which is past, and as a watch in the night.' For if a thousand years are bounded into one day in the eyes of God, then from the world's generation until the rest... up to our own time, as the six days or so are completed (the six-thousandth...)
...the six days are completed (they say, then, that the six-thousandth year extends from Adam down to here; for in the seventh, the seven-thousandth year, they say the judgement will arrive). Therefore all the days are reckoned as thirteen, from our own time up to the 'In the beginning' in which God made the heaven and the earth—above which God, according to their own folly, was in no way at all stripped of being Father and Almighty. But if there are thirteen days in the eyes of God from the world's generation, how does the Wisdom in Sirach say, 'The sand of the seas, and the drops of rain, and the days of eternity—who shall number them?' These things Origen says in his eagerness; and observe what manner of things he trifles with.