Indeed, the Catholic dogma may be said to be summed up in this very formula on which St. Augustine lays so much stress, “Tres et Unus,” not merely “Unum;” hence that formula is the key-note, as it may be called, of the Athanasian Creed. In that Creed we testify to the Unus Increatus, to the Unus Immensus, Omnipotens, Deus, and Dominus; yet Each of the Three also is by Himself Increatus, Immensus, Omnipotens, for Each is that One God, though Each is not the Other; Each, as is intimated by Unus Increatus, is the One Personal God of Natural Religion. That this doctrine, thus drawn out, is of a notional character, is plain; the question before me is whether in any sense it can become the object of real apprehension, that is, whether any portion of it may be considered as addressed to the imagination, and is able to exert that living mastery over the mind, which is instanced as I have shown above, as regards the proposition, “There is a God.” “There is a God,” when really apprehended, is the object of a strong energetic adhesion, which works a revolution in the mind; but when held merely as a notion, it requires but a cold and ineffective acceptance, though it be held ever so unconditionally. Such in its character is the assent of thousands, whose imaginations are not at all kindled, nor their hearts inflamed, nor their conduct affected, by the most august of all conceivable truths. I ask, then, as concerns the doctrine of the Holy Trinity, such as I have drawn it out to be, is it capable of being apprehended otherwise than notionally? Is it a theory, undeniable indeed, but addressed to the student, and to no one else? Is it the elaborate, subtle, triumphant exhibition of a truth, completely developed, and happily adjusted, and accurately balanced on its centre, and impregnable on every side, as a scientific view, “totus, teres, atque rotundus,” challenging all assailants, or, on the other hand, does it come to the unlearned, the young, the busy, and the afflicted, as a fact which is to arrest them, penetrate them, and to support and animate them in their passage through life? That is, does it admit of being held in the imagination, and being embraced with a real assent? I maintain it does, and that it is the normal faith which every Christian has, on which he is stayed, which is his spiritual life, there being nothing in the exposition of the dogma, as I have given it above, which does not address the imagination, as well as the intellect.