1. This is the seventh book of our treatise against the wild extravagance of modern heresy. In order of place it must follow its predecessors; in order of importance, as an exposition of the mysteries of the right faith, it precedes and excels them all. I am well aware how hard and steep is the path of evangelical instruction up which we are mounting. The fears inspired by consciousness of my own incapacity are plucking me back, but the warmth of faith urges me on; the assaults of heresy heat my blood, and the dangers of the ignorant excite my compassion. I fear to speak, and yet I cannot be silent. A double dread subdues my spirit; it may be that speech, it may be that silence, will render me guilty of a desertion of the truth. For this cunning heresy has hedged itself round with marvellous devices of perverted ingenuity. First there is the semblance of devotion; then the language carefully chosen to lull the suspicions of a candid listener; and again, the accommodation of their views to secular philosophy; and finally, their withdrawing of attention from manifest truth by a pretended explanation of Divine methods. Their loud profession of the unity of God is a fraudulent imitation of the faith; their assertion that Christ is the Son of God a play upon words for the delusion of their hearers; their saying that He did not exist before He was born a bid for the support of the world’s philosophers; their confession of God as incorporeal and immutable leads, by a display of fallacious logic, up to a denial of the birth of God from God. They turn our arguments against ourselves; the Church’s faith is made the engine of its own destruction. They have contrived to involve us in the perplexing position of an equal danger, whether we reason with them or whether we refrain. For they use the fact that we allow certain of their assumptions to pass unchallenged as an argument on behalf of those which we do contradict.