RELIGIOUS COMMUNITIESforms of religious education that emphasized doctrinally laden liturgy,
by weekly congregational worship, and by concepts of communal
property.2
Second, the formation of such closely knit communities increasingly
isolated the members of one group from those of another. The bound-
aries created between religious groups by separate bodies of law are
indicative of the rising barriers to interfaith relations at the end of the
Sasanian period. The defensiveness associated with this development
was symbolized by a shared vocabulary of protective walls. The Ma-
gians saw the good fortune of their religion (M.P. den xvarrah) as a
fortress-like enclosure formed by the starry band around the sky, which
protected the good from the attacks of demons.^3 Jews spoke of making
a fence around the Torah,4 and the Nestorian synod of 554 called the
canons "high walls, impregnable fortresses, protecting their guardians
against all danger."^5
Although social barriers based on religious identities were becoming
increasingly formalized, they did not usually coincide with ethnic
identities. Christians could be found among Aramaeans, Persians, Kurds,
Syrians, and Arabs. Aramaeans were pagan, Jewish, Christian, Man-
ichaean, or Muslim. The possession of a common religious identity
allowed a degree of assimilation among people with different ethnic
backgrounds, such as Persian converts from Magianism to Christianity
who submitted to baptism and inhumation but brought traditions of
Persian law with them. Conversely, the possession of a common ethnic
background allowed a degree of similarity to develop among the mem-
bers of different religious groups. The most evident result was the
emergence of similar forms of organization within most religious com-
munities.
Third, the structure of existing religious communities was strength-
ened by the official or semiofficial recognition given to them by the
Sasanian state. Neusner noted that when the Sasanians occupied Iraq
in the third century, they had no local constituency, no tradition for
dealing with minorities, nor experience in using their connections across
the border-"they had no very clear idea of what ,to do with minority
2 For a set of criteria for a religious community, see R. BuIliet, Conversion to Islam
in the Medieval Period (Cambridge, Mass., 1979), pp. 34-35.
J Bailey, Zoroastrian Problems,'pp. 144--47.
4 Pirqe AbhOth, ch. 1, Mishna 1.
5 Chabot, Synodicon, pp. 97, 255.