Thus equipped with a moral armature such as the world had never yet seen, it might have been expected that the triumph of Christianity over the ruins of heathenism would have been as complete and as pure from all admixture of evil as it appears in the great evangelical manifesto commonly called the Sermon on the Mount. But it was not to be so; nor, indeed, created as human nature is, could possibly be. The miraculous virtue of the seed could not change the nature of the soil, and the sweet new wine put into old bottles could not fail to catch a taint from the acid incrustations of the original liquor. _Corruptia optimi pessima_ is the great lesson which history everywhere teaches, and nowhere with a more tragic impressiveness than in the history of the Christian Church. What a rank crop of old wives' fables, endless genealogies, ceremonial observances, worship of the letter, voluntary humilities, and disputations of science, falsely so called, started into fretful array before the spiritual swordsmanship of St. Paul, no reader of the grandest correspondence in the world need be told; but it was not so much from Jewish drivel, Attic subtlety, or Corinthian sensualism, that the corrupting forces were to proceed which in the post-Apostolic age insinuated themselves like a poison into the pure blood of the Church. It is from within that, in moral matters, our great danger flows: if the kingdom of heaven is there, the kingdom of hell is there no less distinctly. The doctrine of Aristotle, and the teaching of history that ALL EXTREMES ARE WRONG, is ever and ever repeated to passion-spurred mortals, and ever and ever forgotten. In the green ardour of our worship we make an idol of our virtue; the strong lines of the particular excellence which we admire are stretched into a caricature; our sublime, severed from all root of soundness, reels over into the ridiculous; we revel and riot and get into an intoxicated excitement with the fruit of our own fancy; and work ourselves from one stage of inflammation to another, till, as our great dramatist says, "Goodness, grown to a pleurisy, Dies of its own too much."