When the Caliph Umar ibn al-Khattab entered Jerusalem in 156-636 AD, while he was still inside the Church of the Holy Sepulcher, the muezzin called for prayer. He called the Patriarch "Safarouni" the Caliph to pray inside the church, but he rejected the offer for fear of following the Muslims later. And the conversion of the church to a mosque, resulting in hurting the feelings of Christians and the denial of freedom of worship in the place became the Caliph Omar to a nearby place outside the church, where the prayer to build the Muslims then a mosque in that spot called "Omar Mosque."