Is it true that the statement "Orthodoxy or death" started as a saying on Mount Athos to protest...

The slogan “Orthodoxy or death” is not a patristic or conciliar teaching; it arose in the 20th century among some monks on Mount Athos as a protest against the Ecumenical Patriarchate’s dialogue with the Roman Catholic Church, notably the 1965 meeting of Patriarch Athenagoras I and Pope Paul VI. The phrase expresses a resolve to uphold the Orthodox faith even at the cost of one’s life, echoing the martyrdom spirit of “better to die than to deny the Truth.” It is a zealous, pastoral warning rather than a doctrinal formula, and the Church’s official position remains that dialogue should be pursued in truth and love without compromising the faith.