Orthodoxy, then, is not any definite creed, or statement of truth. It is not of the letter, but of the spirit. The letter kills. Consequently those who cling to the letter of Orthodoxy kill its spirit. The greatest enemy of Orthodoxy is dead Orthodoxy. The old statements retained after their life is gone,—the old phrases made Shibboleths by which truth is to be forever tested,—these gradually make the whole system seem false to the advancing intellect of the human race. Then heresies come up, just as providential, and just as necessary, as Orthodoxy, to compel the Church to make restatements of the eternal truth. Heresies, in this sense, are as true as Orthodoxy, and make part, indeed, of a higher Orthodoxy. By Orthodoxy, therefore, we do not mean the opinions held by any particular denomination in New England or elsewhere. We do not mean the opinions of New England Calvinists or of Southern Presbyterians; not the creed of Andover, of New Haven, or of Princeton: but we mean that great system of belief which gradually took form in the Christian Church, in the course of centuries, as its standard theology. The pivotal points of this system are sin and salvation. In it man appears as a sinner, and Christ as a Saviour. Man is saved by an inward change of heart, resulting in an outward change of life, and produced by the sight of the two facts of sin and salvation. The sight of his sin and its consequences leads him to repentance; the sight of salvation leads him to faith, hope, and love; and the sight of both results in regeneration, or a new life. This system also asserts the divinity of Christ, the triune nature of God, the divine decrees, the plenary inspiration of Scripture, eternal punishment, and eternal life. § 9. Substantial Truth and Formal Error in all great Doctrinal Systems. Within the last twenty-five years, a new department of theological literature has arisen in Germany, which treats of the history of doctrines. The object of this is to trace the doctrinal opinions held in the Church in all ages. By this course of study, two facts are apparent—first, that the same great views have been substantially held by the majority of Christians in all ages; and, secondly, that the forms of doctrine have been very different. The truths themselves have been received by Christians, as their strength, their hope, and their joy, in all time; but the formal statement of these truths has been wrought out differently by individual intellects. The universal body of Christians has taken care of Christian truth; while the Church Fathers, or doctors, have held in their hands the task of defining it doctrinally for the intellect.