The holy book of
Zoroastrianism
(the word probably means ‘The Injunction [of Zoroaster]’). Only approximately one-quarter of the original is extant. That which has survived is basically the liturgical material which continued in use in regular worship. The content of the ‘canon’ includes material from many ages. There are some pre-Zoroastrian ‘hymns’ (some of the
Yásts
, such as
Yt
. 10 to Mithra) and ‘Litanies’ (
Nyayes
). The anti-demonic law, the
Vendidad
, contains much ancient material, although its present structure was probably Parthian. The liturgy of the
Yasna
is especially ancient, probably much of the substance deriving from Indo-Iranian times. Embedded in the
Yasna
are the seventeen hymns of Zoroaster, the
G
th
s
. They are in two blocks (
Ys
. 28–34 and 43–53) either side of the
Yasna Haptanhait
liturgy, which, if not by Zoroaster, is certainly early. The
G
th
s
are embedded in the
Yasna
the ‘act of [daily] worship’, because that is the liturgical context within which the prophetic hymns have been preserved. Their fragmentary nature, combined with the allusive poetic imagery and metrical form, make them extremely difficult to translate. They are intensely personal in style, passionate outpourings of an individual spirit, following visions of God. For Zoroastrians, they are the most powerful holy
manthras
.
In modern religious practice, Zoroastrians use a
Khorda Avesta
, a collection of essential prayers for daily use by lay people.