The deposition of the Semiarian leaders took place very early in the year 360, and Hilary’s dismissal homewards, one of the same series of measures, must soon have followed. If he had formed the plan of his invective before he left Constantinople, it is not probable that he wrote it there. It was more probably the employment of his long homeward journey. His natural route would be by the great Egnatian Way, which led through Thessalonica to Durazzo, thence by sea to Brindisi, and so to Rome and the North. It is true that the historians, or rather Rufinus, from whom the rest appear to have borrowed all their knowledge, say that Illyricum was one sphere of his labours for the restoration of the Faith. But a journey by land through Illyricum, the country of Valens and Ursacius and thoroughly indoctrinated with Arianism, would not only have been dangerous but useless. For Hilary’s purpose was to confirm the faithful among the bishops and to win back to orthodoxy those who had been terrorised or deceived into error, and thus to cement a new confederacy against the Homoeans; not to make a vain assault upon what was, for the present, an impregnable position. And though the Western portion of the Via Egnatia did not pass through the existing political division called Illyricum, it did lie within the region called in history and literature by that name. Again, the evidence that Hilary passed through Rome is not convincing; but since it was his best road, and he would find there the most important person among those who had wavered in their allegiance to truth, we may safely accept it. He made it his business, we are told, to exhort the Churches through which he passed to abjure heresy and return to the true faith. But we know nothing of the places through which he passed before reaching Rome, the see of Liberius, with whom it was most desirable for him to be on friendly terms. Liberius was not so black as he has sometimes been painted, but he was not a heroic figure. His position was exactly that of many other bishops in the Western lands. They had not denied their own faith, but at one time or another, in most cases at Rimini, they had admitted that there was room in the same communion for Arian bishops and for themselves. In the case of Liberius the circumstances are involved in some obscurity, but it is clear that he had, in order to obtain remission of his exile, taken a position which was practically that of the old Council of the Dedication. Hilary, we remember, had called that Council a ‘Synod of the Saints,’ when speaking of it from the Eastern point of view. But he had never stooped to such a minimising of the Faith as its words, construed at the best, involved. Easterns, in their peculiar difficulties, he was hopeful enough to believe, had framed its terms in a legitimate sense; he could accept it from them, but could not use it as the expression of his own belief. So to do would have been a retrograde step; and this step Liberius had taken, to the scandal of the Church. Yet he, and all whose position in any way resembled his—all, indeed, except some few incorrigible ringleaders—were in the Church; their deflection was, in Hilary’s words, an ‘inward evil.’ And Hilary was no Lucifer; his desire was to unite all who could be united in defence of the truth. This was the plan dictated by policy as well as by charity, and in the case of Liberius, if, as is probable, they met, it was certainly rewarded with success. Indeed, according to Rufinus, Hilary was successful at every stage of his journey. Somewhere on his course he fell in with Eusebius of Vercelli, who had been exiled at the Council of Milan, had passed his time in the region to the East of that in which Hilary had been interned, and was now profiting by the same Homoean amnesty to return to his diocese. He also had been using the opportunities of travel for the promotion of the Faith. He had come from Antioch, and therefore had probably landed at or near Naples. He was now travelling northwards, exhorting as he went. His encounter with Hilary stimulated him to still greater efforts; but Rufinus tells us that he was the less successful of the two, for Hilary, ‘a man by nature mild and winning, and also learned and singularly apt at persuasion, applied himself to the task with a greater diligence and skill.’ They do not appear to have travelled in company; the cities to be visited were too numerous and their own time, eager as they must have been to reach their homes, too short. But their journey seems to have been a triumphal progress; the bishops were induced to renounce their compromise with error, and the people inflamed against heresy, so that, in the words of Rufinus, ‘these two men, glorious luminaries as it were of the universe, flooded Illyricum and Italy and the Gallic provinces with their splendour, so that even from hidden nooks and corners all darkness of heresy was banished.’
In the passage just quoted Rufinus directly connects the publication of Hilary’s masterpiece, usually called the De Trinitate, with this work of reconciliation. After speaking of his success in it, he proceeds, ‘Moreover he published his books Concerning the Faith, composed in a lofty style, wherein he displayed the guile of the heretics and the deceptions practiced upon our friends, together with the credulous and misplaced sincerity of the latter, with such skill that his ample instructions amended the errors not only of those whom he encountered, but also of those whom distance hindered him from meeting face to face.’ Some of the twelve books of which the work is composed had certainly been published during his exile, and it is possible that certain portions may date from his later residence in Gaul. But a study of the work itself leads to the conclusion that Rufinus was right in the main in placing it at this stage of Hilary’s life; this was certainly the earliest date at which it can have been widely influential.