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Page 39. " a pure Patmos "
John of Patmos, by Jean Fouquet
Public DomainJohn of Patmos, by Jean Fouquet

Patmos can refer both to an island in the Aegean Sea and to John of Patmos, believed to be the author of the Book of Revelations in the Bible.  Many Christians believe this man to be the same as the apostle Saint John, the companion of Jesus.