It is certain that Hilary was busily engaged in writing his great work upon the Trinity, and that some parts of it were actually published, during his exile. But as this work in its final form would appear to belong to the next stage of Hilary’s life, it will be well to postpone its consideration for the present, and proceed at once to his share in the conciliar action of the time. We have no information concerning his conduct before the year 358, but it is necessary to say something about the important events which preceded his publication of the De Synodis and his participation in the Council of Seleucia.
It was a time when new combinations of parties were being formed. Arianism was shewing itself openly, as it had not dared to do since Nicæa. In 357 Hilary’s adversaries, Ursacius and Valens, in a Synod at Sirmium, published a creed which was Arian without concealment; it was, indeed, as serious a blow to the Emperor’s policy of compromise as anything that Athanasius or Hilary had ventured. But it was the work of friends of the Emperor, and shewed that, for the moment at any rate, the Court had been won over to the extreme party. But the forces of Conservatism were still the strongest. Within a few months, early in 358, the great Asiatic prelates, soon to be divided over the question of the Godhead of the Holy Spirit but still at one, Basil of Ancyra, Macedonius and others, met at Ancyra and repudiated Arianism while ignoring, after their manner, the Nicene definition. Then their delegates proceeded to the Court, now at Sirmium, and won Constantius back to his old position. Ursacius and Valens, who had no scruples, signed a Conservative creed, as did the weak Liberius of Rome, anxious to escape from an exile to which he had been consigned soon after the banishment of Hilary. It was a great triumph to have induced so prominent a bishop to minimise—we cannot say that he denied—his own belief and that of the Western churches. And the Asiatic leaders were determined to have the spoils of victory. Liberius, of course, was allowed to return home, for he had proved compliant, and the Conservatives had no quarrel with those who held the homoousion. But the most prominent of the Arian leaders, those who had the courage of their conviction, to the number, it is said, of seventy, were exiled. It is true that Constantius was quickly persuaded by other influences to restore them; but the theological difference was embittered by the sense of personal injury, and further conflicts rendered inevitable between Conservatives and Arians.
It was with this Conservative party, victorious for the moment, that Hilary had to deal. Its leaders, and especially Basil of Ancyra, had the ear of the Emperor, and seemed to hold the future of the Church in their hands. Hilary was on friendly terms with Basil, with whom, as we have seen, he had much in common, and corresponded on his behalf with the Western Bishops. He was, indeed, by the peculiar combination in him of the Eastern and the Western, perhaps the only man who could have played the part he undertook. He was thoroughly and outspokenly orthodox, yet had no prejudice in favour of the Nicene definition. He would have been content, like the earlier generation of Eastern bishops, with a simple formulary; the Apostles’ Creed, the traditional standard of the West, satisfied the exigencies even of his own precise thought. And if a personal jealousy of Athanasius and his school on the part of the Asiatic Conservatives was one of the chief obstacles to peace, here again Hilary had certain advantages.
We have seen that there was no personal communication between him and Athanasius; he could ignore, and may even have been ignorant of, the antipathy of Asia to Alexandria. And he was no absolute follower of Athanasius’ teaching. We saw that in some important respects he was an independent thinker, and that in others he is on common ground with the Cappadocians, the heirs of the best thought of such men as Basil of Ancyra. Nor could he labour under any suspicion of being involved in the heresy of Marcellus. It was an honourable tradition of Eastern Christendom to guard against the recrudescence of such heresy as his, which revived the fallacies of Paul of Samosata and of Sabellius, and seemed in Asia the most formidable of all possible errors. Marcellus had forged it as a weapon in defence of the Nicene faith; and if his doctrine were among the most formidable antagonists of Arianism, it may well have seemed that there was not much to choose between the two. And while Athanasius had never condemned Marcellus, and the West had more than once pronounced him innocent, the general feeling of the East was decisively against him, and deeply suspicious of any appearance of sympathy with him. And further, by one of those complications of personal with theological opposition which were so sadly frequent, Basil was in possession of that very see of Ancyra from which the heretic Marcellus had been expelled. Hilary, who was unconcerned in all this, saw a new hope for the Church in his Asiatic friends, and his own tendencies of thought must have been a welcome surprise to them, accustomed as they were to suspect Sabellianism in the West. The prospect, indeed, was at first sight a fair one. The faith, it seemed, might be upheld by imperial support, now that it had advocates who were not prejudiced in the Emperor’s eyes as was Athanasius; and Athanasius himself, accredited by the testimony of Asia, might recover his position.
Yet Hilary was building on an unsound foundation. The Semiarian party was not united. Hilary may not have suspected, or may, in his zeal for the cause, have concealed from himself the fact, that in the doctrine of the Holy Ghost there lay the seeds of a strife which was soon to divide his allies as widely as Arius was separated from Athanasius. And these allies, as a body, were not worthy supporters of the truth. There were many sincere men among them, but these were mixed with adventurers, who used the conflict as a means of attaining office, with as few scruples as any of the other prelates who hung around the court. But the fatal obstacle to success was that the whole plan depended on the favour of Constantius. For the moment Basil and his friends possessed this, but their adversaries were men of greater dexterity and fewer scruples than they. Valens and Ursacius and their like were doing their utmost to retrieve defeat and enjoy revenge. It is significant that Athanasius, as it seems, had no share in Hilary’s hopes and schemes for drawing East and West together. He had an unrivalled knowledge of the circumstances, and an open mind, willing to see good in the Semiarians; had the plan contained the elements of success it would have received his warm support.