From the fourth centuryCEonwards, Jewish calendars began to usefixed
cycles, rules, or schemes, either for the regulation of the intercalation or for the
determination of the beginning of the month. This is evident in dated docu-
ments from this period, where it can be shown that the Jewish month began
not, as previously, from when the new moon wasfirst sighted, but from the
conjunction, which could only have been known from a pre-determined,
schematic table or calculation.^113 A schematic calendar is implicit in a docu-
ment issued by a faction of bishops at the Council of Serdica in 343CE, which
includes a list of dates of the Jewish Passover for a period of 16 years (from 328
to 343). This list implies not only a month beginning at or near the conjunc-
tion, but also a simple scheme for calculating Passover dates, as well as afixed
rule whereby Passover could only occur within the Julian month of March.^114
Another Jewish calendar that underwent schematization in late Antiquity,
in the long term far more important, was the rabbinic calendar, that is to say
the calendar represented in rabbinic literature. The earliest rabbinic sources,
redacted in early third-centuryCEPalestine (e.g. the Mishnah and Tosefta),
present an entirely empirical lunar calendar where the beginning of the month
was determined on the basis of new moon sightings, and the intercalation
decided year by year on the basis of various empirical criteria. In the course of
the Amoraic period (third–fifth centuriesCE), however, a number of rules
appear to have been introduced, determining the length of certain months and
preventing the year from beginning on certain weekdays; a rule of the equinox
is also attested, possibly from the fourth century. These rules, which overrode
the empirical observations, had the effect of gradually transforming the
calendar into afixed scheme: by the time of the redaction of the Palestinian
Talmud (end of the fourth century), the rabbinic calendar consisted largely of
afixed sequence of full and hollow months in alternation.^115 From the sixth
century there is evidence that the beginning of the month in the rabbinic
calendar was based on the conjunction (and no longer on the new moon),
Hierapolis this Jewish festival (which immediately follows Passover) occurred always within the
seventh month of the calendar of Asia, i.e. between 24 March and 22 April (see Ch. 5, Table 5.6),
thus after the equinox.
(^113) A month beginning at the conjunction is implicit in the marriage contract of Antinoopolis
(above, n. 103). The implications of the Catania inscription (Stern 2001: 132–6) will be
reconsidered below (but see general discussion ibid. 139 114 – 43).
Ibid. 74–9, 124–32; see in more detail below. For confirmation of the year of the Serdica
Council as 343CE(and not 342CEas Richard 1974: 318–27), see now Burgess (1999) 241–3,
Lejbowicz (2006) 12, end of n. 29), and Mosshammer (2008) 183.
(^115) Stern (2001) 157–75. The evidence is mainly from the Palestinian and Babylonian Talmuds.
The medieval tradition that thefixed rabbinic calendar was instituted in one piece by a patriarch
named Hillel in the mid-4th c. is not supported by Talmudic sources (ibid. 175–81).
334 Calendars in Antiquity