Mother Miriam, Bishop Athanasius Schneider, and Cardinal Raymond Burke all maintain that Pope Leo XIV is the legitimate pope despite criticizing aspects of his teaching. But church historian Ed Mazza argues that the more fundamental question is whether the current pope is truly a valid pope at all. Drawing on Church history, councils, theologians, and papal writings, Mazza contends that the Catholic Church has consistently taught that a pope cannot officially teach heresy through the Church’s magisterium. Looking at historical examples of saints, bishops, and lay Catholics confronting suspected antipopes and heresy: St. Columba, St. Catherine of Siena, St. Vincent Ferrer. Church history demonstrates that faithful Catholics have sometimes publicly challenged ecclesiastical authorities when they believed the faith was endangered while also stressing the importance of charity toward those who disagree.