The Arians were the most powerful and numerous body of heretics,—­if I may use the language of historians,—­and it was against these that Ambrose chiefly contended.  The great battle against them had been fought by Athanasius two generations before; but they had not been put down.  Their doctrines extensively prevailed among many of the barbaric chieftains, and the empress herself was an Arian, as well as many distinguished bishops.  Ambrose did not deny the great intellectual ability of Arius, nor the purity of his morals; but he saw in his doctrines the virtual denial of Christ’s divinity and atonement, and a glorification of the reason, and an exaltation of the will, which rendered special divine grace unnecessary.  The Arian controversy, which lasted one hundred years, and has been repeatedly revived, was not a mere dialectical display, not a war of words, but the most important controversy in which theologians ever enlisted, and the most vital in its logical deductions.  Macaulay sneers at the homoousian and the homoiousian; and when viewed in a technical point of view, it may seem to many frivolous and vain.  But the distinctions of the Trinity, which Arius sought to sweep away, are essential to the unity and completeness of the whole scheme of salvation, as held by the Church to have been revealed in the Scriptures; for if Christ is a mere creature of God,—­a creation, and not one with Him in essence,—­then his death would avail nothing for the efficacy of salvation; or,—­to use the language of theologians, who have ever unfortunately blended the declarations and facts of Scripture with dialectical formularies, which are deductions made by reason and logic from accepted truths, yet not so binding as the plain truths themselves,—­Christ’s death would be insufficient for an infinite redemption.  No propitiation of a created being could atone for the sins of all other creatures.  Thus by the Arian theory the Christ of the orthodox church was blotted out, and a man was substituted, who was divine only in the matchless purity of his life and the transcendent wisdom of his utterances; so that Christ, logically, was a pattern and teacher, and not a redeemer.  Now, historically, everybody knows that for three hundred years Christ was viewed and worshipped as the Son of God,—­a divine, uncreated being, who assumed a mortal form to make an atonement or propitiation for the sins of the world.  Hence the doctrines of Arius undermined, so far as they were received, the whole theology of the early Church, and obscured the light of faith itself.  I am compelled to say this, if I speak at all of the Arians, which I do historically rather than controversially.  If I eliminated theology and political theories and changes from my Lectures altogether, there would be nothing left but commonplace matter.