When he comes to pray, the Pope will find himself inside a structure that still looks very much like a mosque. “In the name of Allah, the merciful, the compassionate,” reads a wall inscription in Arabic. The prayer niche, which blocks out a window, is in Moorish style and marble pillars hold up a pulpit that has a white and black striped arch similar to what one sees in old mosques in Cairo. It is a far cry from the flat-ceilinged room with the long table depicted in Da Vinci’s The Last Supper.

But the Church’s memory is long. “The Eucharist, the unity of the Church, the Pentecost and the priesthood; all these important things for the Latin Church come from here. It seems like a very modest place but it would have a very strong impact on the lives and mentality of all the Catholics all over the world because the Church was founded here, our life was founded here,” said the Vatican’s Custodian for the Holy Land, Father Pierbattista Pizzaballa.