Monachism was but one application of the doctrine of justification by works, which, by the enthusiasm and superstition of ages, was gradually built into a vast system of sacerdotalism. Through it were eventually opened to the mediæval church sources of illimitable power and wealth by means of the complicated machinery of purgatory, masses for the dead, penances, indulgences, &c., under the sole control of the central head, to which were committed the power of the keys and the dispensation of the exhaustless treasure of salvation bestowed on the church by the Redeemer and perpetually increased by the merits of the saints. To discuss these collateral themes, however, would carry us too far from our subject, and I must dismiss them with the remark that at the period now under consideration there could have been no anticipation of these ulterior advantages to be gained by assuming to regulate the mode in which individual piety might seek to propitiate an offended God. Sufficient motives for the assumption existed in the evils and aspirations of the moment without anticipating others which only received their fullest development under the skilful logic of the Thomists. VIII. THE BARBARIANS. While the Latin church had thus been engaged in its hopeless combat with the incurable vices of a worn-out civilization, it had found itself confronted by a new and essentially different task. The Barbarians who wrenched province after province from the feeble grasp of the Cæsars had to be conquered, or religion and culture would be involved in the wreck which blotted out the political system of the Empire. The destinies of the future hung trembling in the balance, and it might not be an uninteresting speculation to consider what had been the present condition of the world if Western Europe had shared the fate of the East, and had fallen under the domination of a race bigoted in its own belief and incapable of learning from its subjects. Fortunately for mankind, the invaders of the West were not semi-civilized and self-satisfied; their belief was not a burning zeal for a faith sufficiently elevated to meet many of the wants of the soul; they were simple barbarians, who, while they might despise the cowardly voluptuaries on whom they trampled, could not fail to recognize the superiority of a civilization awful even in its ruins. Fortunately, too, the Latin church was a more compact and independently organized body than its Eastern rival, inspired by a warmer faith and a more resolute ambition. It faced the difficulties of its new position with consummate tact and tireless energy; and whether its adversaries were Pagans like the Franks, or Arians like the Goths and Burgundians, by alternate pious zeal and artful energy it triumphed where success seemed hopeless, and where bare toleration would have appeared a sufficient victory.