In the final decades of the last millennium, a Jesuit from Italy came across the ruins of an abandoned monastery in the Syrian Desert. It was to be the start of a forward-thinking Catholic religious community called Al-Khalil that would celebrate hospitality and friendship as its guiding pillars, bringing together Christians and Muslims from across the region during troubled times. Father Paolo Dall'Oglio and the interfaith dialogue he promoted in the monastic outpost of Deir Mar Musa near...