Maj. Avichay Adraee, an Israeli army spokesman, was taken aback when he received a message from a mysterious man writing from the heart of Syria’s bloody civil war.

The man, a Sunni Muslim who created a Facebook page called “Jobar Synagogue,” said he was on a mission to preserve his town’s crown jewel, a centuries-old religious site venerated by the three major religions. Merely contacting the Israelis was an act that could have put his life in danger.

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