And the trial which in these sixty years the Church was going through was well calculated to test her constitution. It is against the spread of false doctrine that S. Ignatius in these epistles so constantly appeals, to the unity of the faithful among each other.(159) He warns them to use only Christian nourishment, and to abstain from strange food, which is heresy.(160) The Church was then continually receiving into her bosom converts at all ages of life, some from the Jews, many more from the Gentiles; among these, therefore, minds brought up in Jewish prejudices, and others which had run havoc in eastern superstitions and systems of philosophy. In the course of these sixty years she probably multiplied many times over in number; and the multiplication was rather by the accession of adults than by the education of children born of Christian parents. The Church was composed of a small minority of the general population scattered at wide intervals over an immense empire; and, so far from being assisted by the civil power, was under constant persecution from it. Whatever force her spiritual government possessed could be exercised only by the voluntary submission of her members. Let us weigh the fact that, under these circumstances, a number of heresies arose. Some were of Jewish, some of Gentile parentage. But we are not here concerned either with their cause or with their matter: we dwell at present only on the fact of their existence. In number they were many; in character most diverse; they arose and flourished in different places. Hardly anywhere was the Church free from them. Let us ask only one question here: by what power were they resisted? The human mind had then the fullest liberty of action in Christians. It was by a free choice—a choice accompanied with danger, and persisted in through suffering—that men became Christians. The liberty which men exercised in becoming Christians they could use further against Christian doctrine, by innovating; by mixing it up with other doctrines, with which, perhaps, their minds had been familiar before their conversion; by developing it after their own fashion. The desire of fame, the self-will of genius, the mere luxury of thought, would offer a continual temptation to such a course. Many, from one motive or another, fell into it. The question which we repeat is, what power prevented the one Church from breaking up under this process of free thought into fragments? These heresies began even while the Apostles were teaching. S. Peter, S. Paul, and S. John speak strongly against them. They swarm in the two generations succeeding the death of S. John. How is it that, at the accession of Marcus Aurelius, Christians having passed the limits of the empire, and being found so far as the wandering tribes of the north, there is still one Church, surrounded, indeed, by a multitude of sects, differing from her and from each other, but herself distinguished and