Byzantine Jerusalem was conquered by the Arab armies of Umar ibn al-Khattab in 638 CE. Among the first Muslims, it was referred to as "Madinat bayt al-Maqdis" ("City of the Temple"), a name restricted to the Temple Mount. The rest of the city "... was called Iliya, reflecting the Roman name given the city following the destruction of 70 CE: "Aelia Capitolina"". Later the Temple Mount became known as "al-Haram al-Sharif", "The Noble Sanctuary", while the city around it became known as "Bayt al-Maqdis", and later still, "al-Quds al-Sharif" "The Holy, Noble". The Islamization of Jerusalem began in the first year A.H. (623 CE), when Muslims were instructed to face the city while performing their daily prostrations and, according to Muslim religious tradition, Muhammad's night journey and ascension to heaven took place. After 13 years, the direction of prayer was changed to Mecca. In 638 CE the Islamic Caliphate extended its dominion to Jerusalem. With the Arab conquest, Jews were allowed back into the city. The Rashidun caliph Umar ibn al-Khattab signed a treaty with Christian Patriarch of Jerusalem Sophronius, assuring him that Jerusalem's Christian holy places and population would be protected under Muslim rule. Christian-Arab tradition records that, when led to pray at the Church of the Holy Sepulchre, one of the holiest sites for Christians, the caliph Umar refused to pray in the church so that Muslims would not request conversion of the church to a mosque. He prayed outside the church, where the Mosque of Umar (Omar) stands to this day, opposite the entrance to the Church of the Holy Sepulchre. According to the Gaullic bishop Arculf, who lived in Jerusalem from 679 to 688, the Mosque of Umar was a rectangular wooden structure built over ruins which could accommodate 3,000 worshipers.