Upavasa

General term denoting fasting, which
is sometimes performed as a prescribed action for particular religious
observances such as festivals and vows
(vrats), and which is also done as
a means of expiating one’s sins.
Although upavasa can refer to total
abstinence from food and drink, it
usually entails modification of one’s
diet. In some cases, as on the festival of
Shivaratri, such “fasting” entails
abstaining from cooked grains, which
are considered such an essential element in a meal that in parts of India
the word rice is also used to mean
“food.” In other cases one will abstain
from certain types of food, such as for
the Santoshi Ma Vrat, in which the person must not eat anything containing
sour or bitter flavors.
When fasting is performed as expiation (prayashchitta), the prescriptions
are usually concerned with the amount
of food eaten rather than the particular
type. The best-known rite of this kind is
the chandrayana, a penitential rite lasting for one lunar month in which the
penitent’s food consumption mirrors
the monthly course of the moon. The
performer begins by eating fourteen
mouthfuls of food on the first day
of the waning moon, then one less
mouthful on each successive day, with
a complete fast on the new moon day.
On each successive day during the
waxing moon, the penitent eats one
more mouthful, finishing at fifteen on
the day of the full moon.