"Every year on the tenth day of the holy month of Muharram, the first on the Islamic lunar calendar, Shia Muslims show a distinctive face of Islam, one that sees spirituality in passion and rituals rather than in the law and the familiar practices that punctuate Muslim lives. . . . No observer of this day, the festival of Ashoura, will remain unaffected by the Shias' display of fealty to their faith."
Vali Nasri, The Shia Revival: How Conflicts within Islam Will Shape the Future