The Use of Reason in Reformed Theology

Natural knowledge of God is inadequate to achieve eternal blessedness. Man convicted by his consciousness of sinfulness learns thereby that God punishes us, but of himself he knows nothing of what God’s will is for the sinner according to His grace. Religio naturalis is thus not salutaris, and can only make man inexcusable, for not accepting revelation. Besides this, man by himself cannot so know what he does know about God through reason and conscience as he ought to know.

—HEIDEGGER (I, 9): “The kind of knowledge of God and of divine things that may be drawn from nature and its principles cannot be so connected with salvation as to be saving. Man the sinner can in no wise know the will and good pleasure of God outside of His revelation. In addition, what man can naturally know about God under the leading of reason and wit, man the yet unsatisfied animal does not know as it can and ought to be known”.

—DANAEUS (Isag. 1, p. 102 ff.) enumerates the distinguishing marks of natural knowledge of God, as distinguished from revealed: “First of all, this knowledge, derived only from God’s visible works or from this world, is true enough; but it is insufficient for salvation, because a peculiar knowledge of redemption is required for salvation. Secondly, this general knowledge does teach that God exists and that He is to be worshipped; for it knows that He is mighty and righteous and wise. But it does not recognise either who this God is or how He is to be worshipped. Thirdly, this general knowledge of God is chiefly sustained by the witness of conscience, which is given by God to every man that cometh into the world (Jn. 1:17). And so, as for a host of reasons this power and voice of our conscience is either suffocated or disappears or is destroyed or corrupted, the same befalls this general knowledge of God in us. Still, it cannot be abandoned, just as the force of conscience cannot be abandoned either. In short, as appears from the above, this general knowledge of God only renders us inexcusable in God’s sight, but does not contain or transmit the doctrine of salvation. By it, we know the one God to be an august majesty and an incomprehensible power. But we do not understand that He is merciful to us in His Son”.

Yet what natural religion teaches about God, although imperfect is not therefore untrue. At the same time “this knowledge”, says COCCEIUS (Summ. Theol., I, 4), “is true although it is not adequate. The things known of God, partly negatively by the setting apart of those that belong to weakness and imperfection, partly by the image, partly by the attribution of inaccessible eminence (for we recognise that He dwells in light inaccessible), are devoid of falsehood: even though there is more in the actual fact than can be perceived by us.”

Natural religion is also useful. On the one hand man is deprived of every excuse, as against God, for not believing in God and not fulfilling His lawful will. On the other hand the natural man who seeks peace with God through religio naturalis will the more joyfully and thankfully accept the revelation of God’s grace, if it is imparted to him. And the regenerate man who has received the revelation of grace and believes in it will be all the better able to understand and see through God’s revelation in nature.

—HEIDEGGER (I, 12): “In short, natural knowledge of God is not useless because not saving. As regards God it has this use, that it renders the man who blames fate, the μεμψίμοιρος, without excuse, ἀναπολόγητος, Rom. 7:20, as regards man it profits to this extent, that both the not yet regenerate seeking God and His salvation in nature, if haply they may grope after and find Him Ac. 17:27, in grace or by the Word of God, the Spirit of God taking the lead, take it up and greet it when found: and the regenerate already taught from God’s word about the true God and the way of His salvation, a return as it were to nature having been instituted, look up more also from God’s admirable works to His power, wisdom and goodness, worship His majesty and put all their trust in the one and only God of Israel, who alone doeth such things.”

Man is aware in his conscience that he is a transgressor against God’s commandment and thereby guilty in God’s sight; and yet by his natural knowledge of God he knows God only as the righteous judge of good and evil. Religio naturalis, then, cannot ensure any man peace with God or be in any sense a religio satisfying to Himself or to man. It actually points beyond itself, since it arouses in man the need and longing for a revelation, by which man must first rightly conceive what it means for a God to exist, and by which he must recognise, that God may also be the sinner’s God, that God will also be sought of the sinner and how He will also be found of him.

—COCCEIUS (S.T., I, 17): “There was every need for revelation, not only that man might be roused to a νόησις and attention to God’s creatures, so as to behold in them the invisible things of God and so feel after God and find Him; but much more that he might learn what it means that God exists, and in this perfection might be aware of the second one which drives him nearer to God, that God may be the sinner’s God; then that he might perceive that grandest glory of God,” which is to will to be sought and found of the sinner; lastly, how He must be sought in order that He may be found. Without this knowledge and faith it is impossible to please God, i.e., to approach Him, to walk with Him, to do things pleasing to Him and to worship Him, Heb. 11:6.” Similarly HEIDEGGER (I, 13).

Man then may with complete certainty recognise what real revelation of God is. If he compares what is proclaimed to him as revelation with his natural consciousness of God, he finds that the latter is satisfied by the former, that revelation enables him to know God in His absolute majesty, his own heart in its sinful misery and at the same time a sure comfort regarding it. But this knowledge is not imparted to man by flesh and blood, but solely by the Spirit of grace, who opens a man’s eyes and directs his heart, that he may achieve a certain knowledge of revealed fact.

—HEIDEGGER (I, 27): “This watchfulness man possesses not by nature but by grace and the Spirit of God, who renders him spiritual and bends his heart thereto and opens his eyes, 1 Jn. 5:7 (it is the Spirit that beareth witness, because the Spirit is truth)”.

The doctrine of the Arminians is rejected (RIISSEN, I, 9): “who lay it down that the light of grace is acquired by the right use of natural light and that by grace we reach glory”. Although in and for itself reason is capable of absorbing supernatural truths, it is impossible for fallen man’s reason to conceive them for itself.

—VOETIUS (I, p. 3): “We presuppose that the supernatural truths of divine faith surpass the reason of man as such. He does not perceive them unless he is raised up and informed by a higher light. But they are not repugnant to him per se or as such, only through the accident of corruption and the wicked disposition which inheres in our mind.”

Generally, then religio naturalis and religio revelata are so related to one another, that the latter is the confirmation of the former (since it absorbs it into itself); and the latter mediates revelation’s point of contact in man. Yet it must by no means be concluded from this that reason, i.e., “the faculty of the rational soul in man by which he apprehends and adjudicates upon things intelligible” (VOETIUS I, 1), may in any way be the principle of knowledge by faith. Not for a moment can this be said of the reason illumined by revelation. On the contrary, the sole principle of religious knowledge must be the light from which even the Christian’s reason has its illumination, namely, revelation; or (since as a matter of order God only reveals Himself by the Word) the Word of Holy Scriptures.

—VOETIUS (I, 3–4): “With these provisos we say that no human reason is the principle by which or through which or in consequence of which or by reason of which we believe, or the foundation or law or norm of what is to be believed, by the prescription of which we judge”.

—HEIDEGGER (I, 33) says that “we must not judge by reason even healed by grace, but according to the principle admitted by illuminated reason, namely, according to Scripture.”

—RIISSEN (I, 11, 1) quotes the following arguments: “Although reason is the instrument or the means by which we may be led to faith, it is not the principle on which dogmas of faith are proved or the foundation on which they rest: (1) (because) the reason of unregenerate man is blind as regards law, Eph. 4:17, 18 (… ye no longer walk … in the vanity of the mind, being darkened in understanding, alienated from the life of God because of the ignorance that is in (you), because of (the) hardening of (your) heart), Rom. 8:7 (the mind of the flesh is enmity against God), Eph. 5:8 (ye were once darkness …), 1 Cor. 2:14 (the natural man receiveth not the things of the Spirit of God; (for) they are foolishness unto him); (2) the mysteries of faith are above the sphere of reason, and to them animal man cannot rise; (3) faith is ultimately resolvable not into reason, so that I ought to believe because I thus understand and grasp, but into the Word, because God thus speaks in Scripture; (4) reason cannot be the norm of religion, either as corrupt (because it is not only beneath faith but against it), or as sound (because such reason is not found in corrupt man).”

Thus “the solid and sure architectonic principle of theology” is “divine revelation” (COCCEUIS Aphor. prolixiores, 11, 7) and revelation mediated by the Word. “Ordinarily God reveals nothing apart from the Word” (COCCEIUS ibid. II, 8).

Of course, Christianity is called by the apostle a “reasonable service”, Rom. 12:1. This, however, must only imply that it consists not in Levitical ordinances, usages and works, but in the worship of God in spirit and truth. In consequence of this, on the other hand, it must also be insisted that Christianity is not directed against reason, that it would not kill it or set it aside, but that it would rather work upon man directly through reason, i.e., not magically but morally.

—HEIDEGGER (I, 39): “The Christian religion is indeed a reasonable service (cultus) Rom. 12:11 not because it is built up from reason or to its norm and scale, but because it is not σωματική, σαρκική, as Israel’s was in part, but inward, spiritual. Thus faith conquers reasoning and leads every reason captive to obedience in Christ, yet so that it does not remove sobriety and light of mind or truth naturally known, but actually conquers by it, by the leading of God’s Spirit and His Word. In revealing God does not push men about like ζῶα ἄλογα or automata, but He speaks to φρόνιμοι, 1 Cor. 10:15 (who can judge what an apostle says). Faith does not destroy reason but stimulates it, does not get it involved but directs it, does not blind the mind but illuminates it.”

Hence the use of reason in theology is perfectly justified. By it (1) the true God must be proved to be the author of revelation; (2) the logical harmony or (and of course it holds only on the supposition of faith!) the rationality of revealed truths must be set forth; (3) the connection of conclusions resulting from each of them is to be developed; and (4) the entire natural, historical, linguistic, etc., knowledge of theology to be made use of. But only faith makes it possible for man to use reason in this correct way and, in dealing with truths which belong only to revelation, to limit it to such an usus organicus, in which illumined and led by the Holy Spirit it adopts revelation, distinguishes the true from the false by the plumb-line of the Word of God, scientifically illumines the mysteries of faith and demonstrates the connection of the separate truths of faith.

—HEIDEGGER (I, 39): “Illumined reason is of no contemptible use to theology. And its chief use consists in the fact that forthwith it brings forth from its own treasury arguments on behalf of faith. This happens in four ways. Firstly, reason urged and directed by the Spirit of God through sure and undoubted criteria and signs of divinity discovers that he who reveals the way of salvation, God, is not an imposter, demon or man suspected of falsehood. Secondly, illumined reason puts forth arguments for the principles of Christian faith, by which it shows to the unbelieving of those who embrace it its worthiness of credit, which is not a thing impossible, irrational or contrary to man’s uncorrupted nature; and it dissolves subtleties adduced to the contrary by a perverse reason. Thirdly, reason occasionally proceeds in accordance with its own principles by collecting suitable arguments on behalf of faith, in those matters which are known both by faith and by reason; or arguments at least known by faith, which stimulates reason in many, are confirmed by reason. Fourthly, in a word reason, accompanying the use of words and of the things signified by these words, whether natural ideas and reasons which we have of and for the things and which revelation presupposes, has power of judgment on equal terms, i.e., those considered apart from construction or conjunction. Use is the judge in familiar words which are not proper and peculiar to revelation. Faith alone judges upon the supernatural construction and conjunction of simple words or terms which belong to revelation alone. The H. Spirit alone secures our right use of reason and the propriety of our faith.” The result of this is that “the use of reason in things which depend on sheer, pure revelation is merely instrumental (organicus)”, i.e., “(1) a man humbly receives and tests revelation in the bosom of reason by the previous Spirit and His Word; (2) in the doctrine of religion reason is an instrument for judging true and false, certain and uncertain, etc., but only if preceded by the light of the divine Word and the inward illumination of the H. Spirit; (3) by the aid of languages and the arts reason throws light upon mysteries solidly proved from the Word of God; (4) reason compares one word of God with another word of God, the OT with the NT, etc., one dogma of faith with another.”

—RIISSEN (I, 11): “The use of human reason in theology is (1) to perceive things revealed, Mt. 13:51 (Have ye understood these things?… Yea!); (2) to compare them with other things, Ac. 17:11 (received the word with all readiness, examining the scriptures daily whether these things were so); (3) to explain, Neh. 8:8 (they read in the book … and they gave the sense so that they understood the reading); (4) to distinguish the false; for it is necessary to search out things that differ, Phil. 1:10 (prove or approve the things that differ); (5) to clear it of objections, Rom. 9 (the ‘God forbids!’).”

Thus by believing surrender to revelation and by a use of reason which puts reason at the service of faith in revelation there grows up a theologia revelata, which, as the first rightly to prove that “natural theology” is preliminary knowledge of God in its true significance, is “the doctrine of God reconciling man the sinner to Himself in Christ and duly to be known of him and worshipped in godly-wise, a doctrine taught of God who reveals it by His Word, and purely instituted as in His presence for man the sinner’s salvation and for the glory of God’s name” (HEIDEGGER I, 14).

On this view theology is a science which rests essentially on the facts of revelation and is meant to be not a pure awareness but a life. Hence it does not, like the purely human science, belong only to a spiritual power of man’s. It pertains to his whole personality, so that in cultivating it the whole man with all the powers of his spiritual and moral life must play his part with reason and understanding, with heart and soul, with knowledge and conscience.

—TURRETIN (I, vi, 4): “None of the intellectual functions as treated in ethics and contradistinguished from each other can constitute the true and proper genus of theology. (1) All these habits are habits of knowing. But theology is a habit not of knowing but of believing. (2) Natural habits were discovered and developed by the ingenuity of man. Theology is supernatural and θεόδοτος; its principle is not human reason but divine revelation. (3) They are all theoretical or practical simply. Theology is of a mixed category, partly theoretical, partly practical. But although theology cannot properly and strictly be called any one of these habits, it is nevertheless well said that it includes them all in itself in an eminent degree.”

Since theology has also to acknowledge and to expound what belongs to natural religion, we may distinguish between “simple (pure) articles”, which rest purely upon revelation, and “mixed articles”, in the exposition of which reason too has its substantial share. Only it must be maintained that the basic doctrines of theology (Trinity, Fall of human race, Redeemer, True Blessedness and the Single Way to it) may be known purely from revelation, and that withal Holy Scripture in every part of its doctrinal system is the sheer authority.

—ALSTED (Theol. Didact., p. 7): “Since theological questions are of two kinds, simple and mixed, of which the former consist of purely theological terms, the latter of a theological term and a philosophical, no one of sound mind could fail to see that philosophy can be applied to proof only in the latter category, in the former merely to assertion and explanation.”


Taken and adapted from: Reformed Dogmatics, by Heinrich Heppe, and translated by G. T. Thomson (2007), 3–11.