MISSIONS, is the term used to denote organized efforts for the spread of a religion, those who carry out the work being known as missionaries. Both "missions" and "missionaries" have hence come to be used of similar propagandist work in other spheres (e.g., "a missionary of peace"). Not only Christianity, but also Buddhism, Zoroastrianism and Islam are, or have been, mis sionary religions. The phrase "foreign missions" customarily used indicates that the work is carried on in countries which are foreign relatively to those from which it emanates, though the increasingly equal partnership of the younger Churches of the East and Africa with the older Churches of the West tends to render the words "foreign missions" slightly misleading. The history of Christian missions may, for practical purposes, be divided into three chief periods : (I) the primitive, (2) the mediaeval, and (3) the modern.
Christian missions begin with Jesus Christ, in whom the uni versalistic religion found in the nobler Judaism (e.g., in "second" Isaiah, some of the Psalms and Jonah) achieved its fulfilment. In His person, work and teaching the unity, holiness, and love, of God, the forgiveness of sins, the ideal of human conduct and the divine order into which the world is to be transformed, are all expressed freed from local and racial limitation. The initial failure of the Palestinian Church to see the universal character of the Christian message was forgotten in the spontaneous move ment of expansion in which Stephen, Philip and Barnabas led, followed by the greatest of all missionaries, the apostle Paul, who evangelized a large part of Asia Minor and the most important cities of Greece. The refusal of Paul to bind upon the Gentile converts Jewish customs such as circumcision marked a decisive movement in Christian history. From this point Christianity pushed its way rapidly into all the great centres of population. We should remember the great number of Greek Jews converted at Pentecost (Acts ii.), and scattered subsequently to the ends of the Roman world.
A famous testimony to the spread of Christianity is that of the younger Pliny, who in his letter to Trajan (A.D. 112) records that
Christianity had taken such a firm hold of the province that its influence had penetrated to remote country districts, pagan festi vals were almost entirely neglected, and animals for sacrifice could hardly find purchasers. Harnack in his Expansion of Chris tianity estimates the hold obtained by Christianity in the countries of the Roman Empire at the end of the third century as follows : (I) Christians numbered nearly one half of the population and Christianity was the standard religion of the people in most of Asia Minor, in the part of Thrace that lay over against Bithynia, in Armenia and in the city of Edessa. (2) Christianity claimed a very material part of the population, influenced the leading classes and held its own with the other religions in Antioch and Crete, Syria, Cyprus, Alexandria together with Egypt and the Thebais, Rome and lower Italy, parts of central Italy, Proconsular Africa and Numidia, Spain, the maritime parts of Greece, and the southern coasts of Gaul. (3) Christians were sparsely scattered in Palestine, Phoenicia, Arabia, certain parts of Mesopotamia, the interior districts of Greece, the provinces in the north of Greece, the northern part of central Italy, and the provinces of Maure tania and Tripolis. (4) Christianity was weak or barely existent in the regions to the north and north-west of the Black Sea, the western part of upper Italy, middle and upper Gaul, Belgium, Germany, Rhoetia and the towns of ancient Philistia.
After the end of the third century missionary enterprise was carried on chiefly on the borders of the Empire. Among the most famous missionaries of this period were Gregory the Illuminator, the apostle of Armenia, about A.D. 300, Ulfilas the apostle of the Goths, about 325, Chrysostom, who founded at Constantinople in A.D. 404 a training school for native Gothic evangelists, Martin of Tours, who evangelized central Gaul, and Patrick, a Scot or Briton, who was taken to Ireland a captive, escaped and became a monk in France, returned to Ireland as a missionary and is traditionally held to be the man who made Ireland the "isle of saints."