("the route of the moon") A one-month penitential ritual (prayashchitta) in which the penitent's food intake corresponds to the monthly cycle of the moon.
On the first day of the waning moon, a person who observes this ritual eats fourteen mouthfuls of food, then one fewer mouthful on each subsequent day until the new moon day, when a full fast (upavasa) is observed.
The penitent consumes one additional mouthful each day during the waxing moon, until he reaches fifteen mouthfuls on the full moon day.
Given the little food available in the middle of the month, this is a pretty harsh penance.
This penance was prescribed in the dharma literature as an atonement for certain types of sexual misconduct, such as having sexual relations with a woman from the same gotra (mythic lineage), marrying a woman from one's maternal grandfather's gotra, or marrying the daughter of one's maternal uncle or paternal aunt.
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