Halakhah sobre Êxodo 9:31

When we investigate the Torah’s year, we find written “This month shall be for you the beginning of months” (Exodus 12:2), so it is first of the months of the year. It is also written “This day you depart, in the month of ripening” (ibid. 13:4), and “Observe the month of ripening” (Deuteronomy 16:1). The explanation is that Israel counts by lunar months, and the month in which the barley ripens in the Land of Israel is the first of the year’s months. The beginning of that month is the beginning of the year, whether the equinox has passed or not. However, in order to perform the waving of the Omer ⁷⁸ The Omer waving took place on the second day of Passover, the sixteenth of Nisan (Leviticus 23:10–11). the court should ensure that Passover will occur when the barley has ripened.⁷⁹ There are exceptions to this requirement. See Ibn Ezra’s commentary to Exodus 12:2 and to Deuteronomy 15:1. Most years the ripening coincides with the equinox, but sometimes they are separated slightly because of an abundance of rain or because of drought.