These labors were directed to the improvement of jurisprudence, and the final extinction of Paganism as a tolerated religion.  He gave to the Church and to Christianity a new prestige.  He rooted out, so far as genius and authority can, those heresies which were rapidly assimilating the new religion to the old.  He was the friend and patron of those great ecclesiastics whose names are consecrated.  The great Ambrose was his special friend, in whose arms he expired.  Augustine, Martin of Tours, Jerome, Gregory Nazianzen, Basil, Chrysostom, Damasus, were all contemporaries, or nearly so.  In his day the Church was really seated on the high-places of the earth.  A bishop was a greater man than a senator; he exercised more influence and had more dignity than a general.  He was ambassador, courtier, and statesman, as well as prelate.  Theodosius handed over to the Church the government of mankind.  To him we date that ecclesiastical government which was perfected by Charlemagne, and which was dominant in the Middle Ages.  Anarchy and misery spread over the world; but the new barbaric forces were obedient to the officers of the Church.  The Church looms up in the days of Theodosius as the great power of the world.

Theodosius is lauded as a Christian prince even more than Constantine, and as much as Alfred.  He was what is called orthodox, and intensely so.  He saw in Arianism a heresy fatal to the Church.  “It is our pleasure,” said he, “that all nations should steadfastly adhere to the religion which was taught by Saint Peter to the Romans, which is the sole Deity of the Father, the Son, and Holy Ghost, under an equal majesty; and we authorize the followers of this doctrine to assume the title of Catholic Christians.”  If Rome under Damasus and the teachings of Jerome was the seat of orthodoxy, Constantinople was the headquarters of Arianism.  We in our times have no conception of the interest which all classes took in the metaphysics of theology.  Said one of the writers of the day:  “If you desire a man to change a piece of silver, he informs you wherein the Son differs from the Father; if you ask the price of a loaf, you are told in reply that the Son is inferior to the Father; if you inquire whether the bath is ready, the answer is that the Son was made out of nothing.”  The subtle questions pertaining to the Trinity were the theme of universal conversation, even amid the calamities of the times.

Theodosius, as soon as he had finished his campaign against the Goths, summoned the Arian archbishop of Constantinople, and demanded his subscription to the Nicene Creed or his resignation.  It must be remembered that the Arians were in an overwhelming majority in the city, and occupied the principal churches.  They complained of the injustice of removing their metropolitan, but the emperor was inflexible; and Gregory Nazianzen, the friend of Basil, was promoted to the vacant See, in the midst of popular grief and rage.  Six weeks afterwards Theodosius expelled from all the churches of his dominions, both of bishops and of presbyters, those who would not subscribe to the Nicene Creed.  It was a great reformation, but effected without bloodshed.