How and when can religious times become focal points for communal violence? In the context of Hindu-Muslim riots in India, I argue that incompatible ritual holidays where one religion's rituals are at odds with the other religion (e.g. sacrificing cows or engaging in processions with idolatry) explains the positive effect of sacred time on religious rioting. Holidays with incompatible rituals provide doctrinal differences that make riots more likely. I provide support for this argument by (1) analyzing riot data across 100 years of Hindu-Muslim riots, (2) exploring individual-level surveys responses on holidays, and (3) describing the way different holiday rituals play a role in violence. By focusing on the content of religion, this paper demonstrates how particular religious holidays can provide the underlying conditions that riot entrepreneurs use to incite religious violence.