Of the ancient Churches in Western Asia at the time of the Muhammadan conquest, there still survive about 150,000 Nestorians, [187] and their number would have been larger but for the proselytising efforts of other Christian Churches; the Chaldees who have submitted to the Church of Rome number 70,000, in 1898 the Nestorian Bishop Mār Jonan, with several of the clergy and 15,000 Nestorians were received into the Orthodox Russian Church; and numbers of Nestorians have also become Protestants. [188] The Jacobite Patriarch of Antioch exercises jurisdiction over about 80,000 members of this ancient Church, while 25,000 families of Uniat Jacobites obey the Syrian Catholic Patriarch. [189] Belonging to the Greek Orthodox Church, there are 28,836 families under the Patriarch of Antioch and more than 15,000 persons under the Patriarch of Jerusalem, [190] while the Melchites or Greek-Catholics number about 130,000. [191] The Maronite Church, which has been in union with the Roman Catholic Church since the year 1182, has a following of 300,000. [192] The marvel is that these isolated and scattered communities should have survived so long, exposed as they have been to the ravages of war, pestilence and famine, [193] living in a country that was for centuries a continual battle-field, overrun by Turks, Mongols and Crusaders, [194] it being further remembered that they were forbidden by the Muhammadan law to make good this decay of their numbers by proselytising efforts—if indeed they had cared to do so, for they seem (with the exception of the Nestorians) even before the Muhammadan conquest, to have lost that missionary spirit, without which, as history abundantly shows, no healthy life is possible in a Christian Church. It has also been suggested that the monastic ideal of continence so widespread in the East, and the Christian practice of monogamy, together with the sense of insecurity and their servile condition, may have acted as checks on the growth of the Christian population. [195] Of the details of conversion to Islam we have hardly any information. At the time of the first occupation of their country by the Arabs, the Christians appear to have gone over to Islam in very large numbers. Some idea of the extent of these early conversions in ʻIrāq for example may be formed from the fact that the income from taxation in the reign of ʻUmar was from 100 to 120 million dirhams, while in the reign of ʻAbd al-Malik, about fifty years later, it had sunk to forty millions: while this fall in the revenue is largely attributable to the devastation caused by wars and insurrections, still it was chiefly due to the fact that large numbers of the population had become Muhammadan and consequently could no longer be called upon to pay the capitation-tax. [196]