But how long that morning [of Creation] had existed we do not know, unless we appeal to the Book of Abraham, translated by Joseph Smith from Egyptian papyrus. That tells us in plainness that the way the Lord and the celestial host reckon time, was by the revolutions of a certain great central body called Kolob, which had one revolution on its axis in a thousand of our years, and that was one day with the Lord, and when the Lord said to Adam, "in the day thou eatest thereof thou shalt surely die," the Book of Abraham says it was not yet given unto man the true reckoning of time, and that it was reckoned after the Lord's time that is one thousand years with us was a day with him, and that Adam, if he partook of the forbidden fruit, was to die before that day of a thousand years should expire.