The great cycle of the moon is 21 years; it has 7 small cycles each containing 8 years. The total of the days of the lunar month is 29½ days, 40 minutes, and 73 parts. Each constellation serves the days of the lunar month for 2 days and 8 hours; three constellations serve for 7 days. The chief which begins on the new moon (of the lunar month) is the same which concludes at the end of the lunar month. The moon becomes new at every Molad, once at night and the next time by day, || and this is their sign: "And it was evening and it was morning" (Gen. 1:5). Between one Molad and (the corresponding) Molad in the ensuing year (there elapse) 4 days, 8 hours, and 876 parts.