Jub. 6:45 And all the days of the commandment will be two and fifty weeks of days, and (these will make) the entire year complete.46

Thus it is engraven and ordained on the heavenly tables. And there is no neglecting (this commandment) for a single -year or from year to year. 47 And command thou the children of Israel that they observe the years according to this reckoning-three hundred and sixty-four days, 48 and (these) will constitute a complete year, and they will not disturb its time from its days and from its feasts; 49 for everything will fall out in them according to their testimony, and they will not leave out any day nor disturb any feasts. 50 But if they do neglect and do not observe them according to His commandment, then they will disturb all their seasons, and the years will be dislodged from this (order), 51 [and they will disturb the seasons and the years will be dislodged] and they will neglect their ordinances. 52 And all the children of Israel will forget, and will not find the path of the years, and will forget the new moons, and seasons, and sabbaths, and they will go wrong as to all the order of the years.