“[Addressing a Muslim]: Almighty God, who desires all men to be saved and no one to be lost, appreciates in us above all the fact that, after having loved Him, we love our brother, and that what we do not want to be done to us we do not do to others. You [a Muslim] and we owe each other this charity, above all because we believe and confess the one God, admitted in different ways, and we praise and venerate Him every day, as Creator and Ruler of this world”

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Pope St. Gregory VII

Letter to Emir Al-Nacir, 1076 AD

as 23by St. John Paul II