Doctor of the church

Doctor of the Church (Latin doctor "teacher") is a title given by the Catholic Church to saints whom they recognize as having been of particular importance, particularly regarding their contribution to theology or doctrine.

Some other churches have similar categories with various names.

In the Western church four eminent "Fathers of the Church" attained this honour in the early Middle Ages: Saint Gregory the Great, Saint Ambrose, Saint Augustine, and Saint Jerome. The "four Doctors" became a commonplace among the Scholastics, and a decree of Boniface VIII (1298) ordering their feasts to be kept as doubles in the whole Church is contained in his sixth book of Decretals (cap. "Gloriosus", de relique. et vener. sanctorum, in Sexto, III, 22).

In the Eastern Church three Doctors were pre-eminent: Saint John Chrysostom, Saint Basil the Great, and Saint Gregory Nazianzen. The feasts of these three saints were made obligatory throughout the Eastern Empire by Leo VI the Wise. A common feast was later instituted in their honour on 30 January, called "the feast of the three Hierarchs". In the Menaea for that day it is related that the three Doctors appeared in a dream to John Mauropous, Bishop of Euchaitae, and commanded him to institute a festival in their honour, in order to put a stop to the rivalries of their votaries and panegyrists. This was under Alexius Comnenus (1081–1118; see "Acta SS.", 14 June, under St. Basil, c. xxxviii). But sermons for the feast are attributed in manuscripts to Cosmas Vestitor, who flourished in the tenth century. The three are as common in Eastern art as the four are in Western. Durandus (i, 3) remarks that Doctors should be represented with books in their hands. In the West analogy led to the veneration of four Eastern Doctors, Saint Athanasius being added to the three hierarchs.

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