Archibald Alexander (1772–1851) on Natural and Moral Inability

…many adopted with readiness a distinction of human ability into natural and moral. By the first they understood merely the possession of physical powers and opportunities; by the latter, a mind rightly disposed. In accordance with this distinction, it was taught that every man possessed a natural ability to do all that God required of him; but that every sinner laboured under a moral inability to obey God, which, however, could not be pleaded in excuse for his disobedience, as it consisted in corrupt dispositions of the heart, for which every man was responsible. Now this view of the subject is substantially correct, and the distinction has always been made by every person, in his judgments of his own conduct and that of others. It is recognized in all courts of justice, and in all family government, and is by no means a modern discovery. And yet it is remarkable that it is a distinction so seldom referred to, or brought distinctly into view, by old Calvinistic authors. The first writer among English theologians that we have observed using this distinction explicitly, is the celebrated Dr. Twisse, the prolocutor of the Westminster Assembly of Divines, and the able opposer of Arminianism, and advocate of the Supralapsarian doctrine of divine decrees. It was also resorted to by the celebrated Mr. Howe, and long afterwards used freely by Dr. Isaac Watts, the popularity of whose evangelical writings probably had much influence in giving it currency. It is also found in the theological writings of Dr. Witherspoon, and many others, whose orthodoxy was never disputed. But in this country no man has had so great an influence in fixing the language of theology, as Jonathan Edwards, president of New Jersey College. In his work on "The Freedom of the Will," this distinction holds a prominent place, and is very important to the argument which this profound writer has so ably discussed in that treatise. The general use of the distinction between natural and moral ability may, therefore, be ascribed to the writings of President Edwards, both in Europe and America. No distinguished writer on theology has made more use of it than Dr. Andrew Fuller; and it is well known that he imbibed nearly all his views of theology from an acquaintance with the writings of President Edwards. And it may be said truly, that Jonathan Edwards has done more to give complexion to the theological system of Calvinists in America, than all other persons together. This is more especially true of New England; but it is also true to a great extent in regard to a large number of the present ministers of the Presbyterian church. Those, indeed, who were accustomed either to the Scotch or Dutch writers, did not adopt this distinction, but were jealous of it as an innovation, and as tending to diminish, in their view, the miserable and sinful state of man, and as derogatory to the grace of God. But we have remarked, that in almost all cases where the distinction has been opposed as false, or as tending to the introduction of false doctrine, it has been misrepresented. The true ground of the distinction has not been clearly apprehended; and those who deny it have been found making it themselves in other words; for that an inability depending on physical defect, should be distinguished from that which arises from a wicked disposition, or perverseness of will, is a thing which no one can deny who attends to the clear dictates of his own mind; for it is a self-evident truth, which even children recognize in all their apologies for their conduct.

Archibald Alexander, “The Inability of Sinners,” in Theological Essays: Reprinted from the Princeton Review (New York & London: Wiley and Putnam, 1846), 266–67.

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For an example where the distinction has been misrepresented, see Canon XXI in the Formula Consensus Helvetica (1675).