"But it is, after all, the general purpose of exhibiting the triumph of moral power over all physical and inferior spiritual force, in the descent of Christ into hell, which gives my design the complex character of a mythic, heroic, and Christian poem, and, at the same time, constitutes the unity of its parts. The ancients, whose representative types I introduce, knew and appreciated but two kinds of power, brute or physical, and spiritual, including all occult and supernatural efficacy, and strength of intellect and will. Virtue, triumphant by the aid of adventitious force, or relying upon unconquerable pride and disdain to resist it, was the highest reach of their dynamic conceptions. Moral power is properly a Christian idea. It is not, therefore, without what I conceive to be a true as well as a poetic apprehension of the design of the Descent into Hell, that the heroes of profane, and the not fabulous Titans of sacred antiquity, by their rivalries and contentions, brought together in arms for a trial of their comparative strength, are suddenly confronted with a common and dissimilar antagonist, and 'all strength, all terror, single or in bands, that ever was put forth' opposed to that novel, and, save in the Temptation, hitherto untested power, represented by Christ, the author of the theory and master of the example. "He is not supposed to appear among them 'grasping in his hand ten thousand thunders,' but endued with an equal power, the result and expression of perfect virtue and rightful authority. His triumph is attributed neither to natural, nor to supernatural power; but to moral superiority, evincing itself in His aspect, and exercising its omnipotence upon the soul and conscience. That in the conception of a great Christian poet, His appearance among the rebel angels in Heaven was distinguished by the former attributes, is due, perhaps, to the heroic prejudice of a mind thoroughly imbued with the spirit of pagan writers, and of the Hebrew Scriptures." The volume opens with this noble invocation, in which there is fit recognition of Dante and Milton, whose lips aforetime for such song had been touched by the divinest fire: