Sivan

Sivan is the third month of the Hebrew year, falling in late spring, roughly May to June, and aligned in tradition with the sign of Gemini. It counts thirty days. Sivan opens with the festival of Shavuot on the sixth, the culmination of the counting of the Omer, which celebrates the giving of the Torah at Sinai and, in its agricultural aspect, the wheat harvest and the bringing of first fruits. The name Sivan, adopted in the Babylonian period, is glossed with the sense of brightness. The Hebrew calendar is lunisolar, its months set by the moon and kept in step with the solar year by an added month in leap years, so that Shavuot always falls in the season of harvest. These are the observances of the Jewish calendar tradition, in which Sivan marks the revelation at Sinai.

Sivan is named, like the other Babylonian-derived Hebrew month names, from Akkadian usage adopted after the exile, and it holds Shavuot, the Feast of Weeks, on the sixth (and, outside the Land of Israel in traditional practice, also the seventh), marking the conclusion of the forty-nine-day Omer count begun in Nisan. Shavuot is associated in rabbinic tradition, though not stated explicitly as such in the Torah's own text, with the giving of the Torah at Mount Sinai, an event the book of Exodus places in the third month without naming an exact calendar date, a gap later tradition filled by fixing the association to Shavuot's own sixth-of-Sivan observance.

The name comes from the Akkadian Simanu, one of the Babylonian month names adopted wholesale into Hebrew usage. The month runs a fixed 30 days in every year.

The month names are Babylonian. Twelve of them are the Akkadian month names taken into Hebrew during and after the exile, and the biblical books of the return use them freely while the earlier books generally number the months or use a small set of older Canaanite names. The atlas records the borrowing rather than presenting the names as native, because it is one of the clearest visible marks the exile left on Jewish practice.

The Jewish calendar as now kept is calculated rather than observed. Month lengths are fixed by rule except for Cheshvan and Kislev, which absorb the adjustment and may run 29 or 30 days, and a thirteenth month is added in seven years out of nineteen on a fixed cycle so that Passover stays in the spring. A further set of rules, the postponements, shifts Rosh Hashanah off certain weekdays, which is why the year has six possible lengths rather than two.

Sivan holds Shavuot, which the Torah fixes not by a date but by a count of fifty days from Passover, so it is the one pilgrimage festival whose position follows from arithmetic rather than from a stated day of the month. In the fixed calendar the count always lands it on the sixth of Sivan.