But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
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Irenaeus of Lyons
AD 202
And there are some, again, who relegate the death of Adam to the thousandth year; for since "a day of the Lord is as a thousand years".
This is an account of the things formerly created, as also it is a prophecy of what is to come. For the day of the Lord is as a thousand years;
For as Adam was told that in the day he ate of the tree he would die, we know that he did not complete a thousand years. We have perceived, moreover, that the expression, `The day of the Lord is as a thousand years, '