The occasion of the Arian controversy[78] was this.[79] Alexander, bishop of Alexandria, speaking in a very warm manner concerning the Trinity before the presbyters and clergy of his church, affirmed there was “an Unity in the Trinity,” and particularly that “the Son was co-eternal and consubstantial, and of the same dignity with the Father.” Arius, one of his presbyters, thought that the bishop, by this doctrine, was introducing the Sabellian heresy, and therefore opposed him, arguing in this manner: “If the Father begot the Son, he who was begotten must have a beginning of his existence; and from hence,” says he, “it is manifest, that there was a time when he was not; the necessary consequence of which” he affirmed was this,[80] “that he had his subsistence out of things not existing.” Sozomen adds farther, that he asserted, “that by virtue of his free-will the Son was capable of vice as well as virtue; and that he was the mere creature and work of God.” The bishop being greatly disturbed by these expressions of Arius, upon account of the novelty of them, and not able to bear such an opposition from one of his presbyters to his own principles, commanded (“admonished, as president of the council, to whom it belonged to enjoin silence, and put an end to the dispute”) Arius to forbear the use of them, and to embrace the doctrine of the consubstantiality and co-eternity of the Father and the Son. But Arius was not thus to be convinced, especially as a great number of the bishops and clergy were of his opinion, and supported him; and for this reason himself and the clergy of his party were excommunicated, and expelled the church, in a council of near an hundred of the Egyptian and Lybian bishops met together for that purpose, by the bishop, who in this case was both party and judge, the enemy and condemner of Arius. Upon this treatment Arius and his friends sent circular letters to the several bishops of the church, giving them an account of their faith, and desiring that if they found their sentiments orthodox, they would write to Alexander in their favour; if they judged them wrong, they would give them instructions how to believe. Thus was the dispute carried into the Christian church, and the bishops being divided in their opinions, some of them wrote to Alexander not to admit Arius and his party into communion without renouncing their principles, whilst others of them persuaded him to act a different part. The bishop not only followed the advice of the former, but wrote letters to the several bishops not to communicate with any of them, nor to receive them if they should come to them, nor to credit Eusebius,[81] nor any other person that should write to them in their behalf, but to avoid them as the enemies of God, and the corrupters of the souls of men; and not so much as to salute them, or to have any communion with them in their crimes. Eusebius,[82] who was bishop of Nicomedia, sent several letters to Alexander, exhorting