In Christianity, memento mori is depicted in art and architecture in ossuaries, or “bone churches,” lined with human bones and funerary art with symbols such as skulls and hourglasses, reminding believers of their mortality and divine judgment. Christian rites that encourage the practice of memento mori include Lent, a 40-day period of penitence and fasting that precedes the festival of Easter and begins with Ash Wednesday, in which a priest sprinkles ashes on the foreheads of congregants as a reminder of their mortality.