The Thirteenth Biblical Month Adar 2

It is crucial to note that the first new moon after the AVIV is sighted is declared as the new moon of AVIV. Therefore, even when AVIV is found before the vernal equinox the month of AVIV most likely starts on the new moon after the vernal equinox. This is because when AVIV is found before the vernal equinox AVIV has only been found a few days before the vernal equinox. Therefore, 99% of the time the first new moon after the vernal equinox is the new moon that starts the New Year. As a result, it makes it appear that the new moon that starts the first month of the biblical year is determined by the vernal equinox.

However, biblically the emphasis is on the AVIV and not on the vernal equinox. The only exception to the new moon of the first month being before the vernal equinox would happen when the new moon was sighted within a few days after the AVIV was found. This would be in that few days when AVIV was sighted before the vernal equinox and the new moon occurred immediately after the AVIV was sighted. This is a rare occurrence because, the vernal equinox is crucial for the maturing and the ripening of the AVIV. The Northern Hemisphere begins to warm more rapidly when the sun is north of the equator. When this occurs, the Spring weather conditions and temperatures are more favorable for the AVIV to ripen.

A much more common occurrence is when AVIV is sighted much later than the vernal equinox. When this happens the sighting of AVIV is used to add the 13th month, and the current year becomes a leap year. According to the Talmud, the case of using the vernal equinox (Tekufah) alone, to determine whether to add a 13th month or to start the first month was never officially accepted. “Our Rabbis taught: A year may be intercalated on three grounds: on account of the premature state of the corn crops;7 or that of the fruit-trees;8 or on account of the lateness of the Tekufah9 Any two of these reasons can justify intercalation, but not one alone. All, however, are glad when the state of the spring-crop is one of them.10 Rabban Simeon b. Gamaliel says: On account of [the lateness of] the Tekufah. The Schoolmen inquired: Did he mean to say that ‘on account of the [lateness of the] Tekufah’ [being one of the two reasons], they rejoiced,11 or that the lateness of the Tekufah alone was adequate reason for intercalating the year? — The question remains undecided.”( Babylonian Talmud - Mas. Sanhedrin ) This places a much greater emphasis on the Aviv.

Even the Talmud states that the Sanhedrin was more comfortable declaring the thirteenth month when the AVIV had not matured “Any two of these reasons can justify intercalation, but not one alone. All, however, are glad when the state of the spring-crop is one of them.10”( Babylonian Talmud - Mas. Sanhedrin 11b). The primary reason that the Sanhedrin felt more comfortable declaring the thirteenth month when the AVIV had matured, is because, regardless of whether the vernal equinox had already occurred, the Omer wave offering could not be presented to HaShem without the first AVIV harvest. In other words, the priests could not approach the Lord empty handed.

End Notes

(7) This species must be ripe in the mouth of Nisan which is known in the Bible as the Abib (Ex.
XIII,44) the month of ears (of corn), in reference to the ripeness of the corn in that month.
(8) Which should, as a rule, ripen close before ‘Nazareth (Pentecost), the time when the Pilgrims
bring the first fruits to Jerusalem (Num. XXVIII, 26). If it happens that the fruit is unripe, the
year may be intercalated so as to prevent a special journey.
(9) Lit. ‘cycle’, ‘season’. The Jewish Calendar, while being lunar, takes cognisance of the solar
system to which it is adjusted at the end of every cycle of nineteen years. For ritual purposes the
four Tekufoth seasons, are calculated according to the solar system, each being equal to one
fourth of 365 days, viz. 91 days, 71/2 hours. Tekufah of Nisan (Vernal equinox) begins March
21; Tekufah of Tammuz (Summer Solstice), June 21; Tekufah of Tishri (Autumnal equinox),
September 23; Tekufah of Tebeth (Winter Solstice), December 22. Should the Tekufah of
Tammuz extend till after the Succoth Festival, or the Tekufah of Tebeth till the sixteenth of
Nisan, the year would be intercalated, so that the festivals might fall in their due seasons, viz.,
Passover in Spring, Succoth in Autumn.
(10) Because if the corn-crop is already ripe and the intercalation prompted by other reasons, the
prohibition of new produce till after the Omer Offering (v. p. 50, n. 4) according to Lev. XXIII,
14, would be unduly prolonged for another month.
(11) Because if the Tekufah was in order, and the intercalation had been effected for other
reasons, the pilgrims would be subject to wintry weather when returning from Jerusalem after the
Succoth Festival.

By Rabbi Yaakov benYosef ­

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