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In page Pope Gregory X:

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The election of Visconti, after a two-year, nine-month struggle, came as a complete surprise to him, since it took place while he was engaged in the Ninth Crusade at Acre in Palestine with King Edward I of England. Not wanting to abandon his mission, his first action, upon hearing of his election, was to send out appeals for aid to the Crusaders. At his final sermon at Acre just before setting sail for Italy, he famously remarked, quoting Psalm 137: "If I forget thee, O Jerusalem, let my right hand forget her cunning."[citation needed]