any date before 25 March.^120 If, as is generally assumed, section IX of the
Codex represents the dates of Easter that were actually observed in Rome in
this period, we may conclude that thesupputatioRomanadid not determine
the date of Easter, because other criteria—such as the limit of 25 March—
frequently overrode thesupputatio’s dates. It is even possible that in its
original, early fourth-century version, the table of thesupputatioRomana
did not include Easter dates at all, but only lunar data such as the epacts.^121
The annual determination of the date of Easter could thus have been based on
lunar data drawn from thesupputatiotogether with other criteria which may
have been sometimesad hocand (as in 333CE) somewhat unclear.^122
Whatever the extent to which the churches of Alexandria and Rome
adhered, in the period of the Council of Nicaea, to these very different Easter
cycles of 19 and 84 years, the two churches seem also to have differed on other
principles of Easter computation, in particular the‘limits’of Easter Sunday. In
fourth-century Rome, Easter Sunday could only occur within the lunar limits
ofluna XVI–XXII,and within the solar (i.e. Julian calendar) limits of 25
March—21 April.^123 These narrow solar limits (less than one full month)
(^120) On this rule see below, n. 123. Thus in both 330 and 341CE, thesupputatiohas 22 March,
but the Codex of 354 has 19 April; it was only in the next 84-year cycle, in 414 and 425CE, that
thesupputatiodate of 22 March was followed. Likewise, in 357CEthesupputatiohas 23 March,
but the Codex has 30 March; whereas in 441CE, 23 March was observed.
(^121) This suggestion, which I do not know anyone else to have made, is all the more likely if, as
has been argued by H. Stern (1953) 55–7, the 84-yearsupputatiowas originally designed by
astrologers rather than by Christians (see Ch. 6 n. 95). 122
Earlier scholars sought to establish a specific date at which thesupputatioRomanawas
instituted, e.g. 342CE(so Richard 1974: 312–27; see also C.W. Jones 1943: 25–6). However, this
is to assume a formal adoption of the 84-year cycle, whereas I doubt whether the Roman Church
ever sofirmly committed itself to it. Krusch (1880) 31–115 (summary in Mosshammer 2008:
217) attempted to explain the inconsistencies between thesupputatioand the Codex in the early
decades of the 4th c. by positing the existence of an‘older’supputatioRomana; Richard (1974)
argued instead that an octaeteris was in continuous use in Rome from the early 3rd c. until 342
CE; both conjectures, however, are unnecessary and insufficiently supported with evidence.
(^123) The lunar limits ofXVI–XXIIare implicit already in the Roman Easter cycles of the 3rd c.,
and referred to also by Anatolius (see above, near n. 88). The upper limit ofluna XVIconforms
to the chronology of the synoptic Gospels, according to which the Friday of the Crucifixion was
Passover orluna XIV, hence the Resurrection on Sundayluna XVI. But the origins of the solar
limits of 25 March–21 April are less clear. In the 3rd c., Roman cycles assume the lower limit of
21 April but allow Easter before 25 March. The limits 25 March–21 April only emerge in the 4th
c., when they can be inferred from the list of Easter dates in the Calendar Codex of 354, starting
in 312CE; these limits are explicitly mentioned in the entry for 349CEof the Index of Athanasius’
Festal Letters (Martin and Albert 1985: 248–9, although the text actually reads’30 Phamenoth’,
i.e. 26 March, perhaps by confusion with the 26 March Easter date of that year). Although 25
March happens to be the traditional Julian date of the equinox (see Ch. 5 n. 162), it is unclear
whether this upper limit was related to a rule of the equinox, and whether it wasde iurerather
than justde facto. As to the lower limit, the date of 21 April was the festival of the foundation of
the city of Rome (natalisurbis diesorParilia), which although in a certain sense‘pagan’, was still
celebrated by Christians in 4th-c. Rome at least out of local patriotism (Salzman 1990: 155, 184).
This is almost certainly why Easter was not allowed later than 21 April in Rome, because then the
festivities of thenatalisurbis dieswould have clashed, for Christians, with the fast of Lent. For the
Sectarianism andHeresy 405