Natural law's fundamental philosophical claim is that there is an objective moral order; that human beings are not free, on all issues, to construct whatever morality they think fit but are instead constrained by the ordering of nature. In its theological form, natural law claims that there is a God-given moral order against which human beings will be judged.
This article seeks to explore what is at stake in these claims. Why are its defenders keen to assert the objectivity and givenness of the moral order? Natural law is, after all, dangerous. One objection raised by those who believe in the forces of history and progress is that excessive commitment to a given moral order amounts to antiquarian intransigence, defending the injustices of the past. The short answer to that concern is that everything depends on what principles are identified in the given moral order. Arguments about the given equality of human beings were highly effective in the fight against slavery and for education in the eighteenth and nineteenth centuries.
The more serious concern is that if too much is claimed for natural law, the distinctive gospel message is occluded. The Christian message is reduced to mere natural morality and Christ's challenges to forsake natural goods in favour of spiritual ones are screened out.
However, despite the dangers, the theological version of natural law is important because it establishes the justice of God, and thereby provides a criterion by which both human beings and therefore by extension human legal regimes may be judged. It provides a theological account of the intuition that some things are absolutely wrong, and is, this paper seeks to argue, a necessary corollary of the doctrine that human beings are accountable to God and will be judged by God.
Everything turns on whether natural law is seen as a way of asserting that people can know enough about God and enough about what God requires of them to be able to live justly and attain salvation, or whether natural law is seen as a way of asserting that God would not be acting unjustly if God were to exclude from heaven sinful human beings.Footnote 1
Is natural law being used to say all can be saved ‘by their own efforts’ or to say God would be just if God were to exclude from His presence all human beings because ‘all have sinned, and fall short of the glory of God’ (Rom. 3:23)? The person who is often credited with baptising the notion into Christian thought, Thomas Aquinas, clearly has the latter point in view (ST III.supp.90.2). In ST I-II.79, his argument is structured so as to make the point that human beings are responsible for the sin which separates them from God and that God is to be praised for God's gratuitous election of some into friendship with Him.Footnote 2 The position Aquinas wants to defend is that adopted by the Council of Quiercy (853) which decreed that ‘The fact that certain [men] are saved is the gift of the One who saves; the fact that certain [men] are lost is the fault of those who are lost.’
1. Natural law and the justice of God
One of the fundamental maxims of English law is ‘Ignorance of the law is no defence.’ French law expresses the same idea as ‘Nul n'est censé ignorer la loi’. The maxim which Aquinas knew, nullas ligatus nisi mediante scientia (de Ver. 17.3), represents the other side of the coin. Human legal systems have to operate on the basis that everyone is expected to either know, or to have been able to find out through the exercise of reasonable diligence, what the law required of them. Whilst in our over-legislated, bureaucratic societies today such a claim is increasingly a legal fiction, it is essential to the justice of a legal system that its laws should be known or knowable but all who are subject to it.
The same must be true of God.Footnote 3 If God holds people accountable for violations of a given moral order, God's judgments on them for such violations would be just if and only if that moral order was one which they did or could have discerned.
Thus Paul argues explicitly in Romans 2:12 that ‘All who sin apart from the law will also perish apart from the law, and all who sin under the law will be judged by the law.’ How can such perishing be justified? Paul goes on in Romans 2:14 to explain that ‘… when Gentiles, who do not have the law, do by nature the things required by the law, they are a law for themselves, even though they do not have the law, since they show that the requirements of the law are written on their hearts, their consciences also bearing witness, and their thoughts now accusing, now even defending them.’ In other words, even the little that we discern of the moral order apart from Christ is enough to condemn us for our failures to live our lives in accordance with it.
When natural law thinkers made strong claims about the self-evidence of the moral order, it was easy to defend God's justice on this basis. If the essentials of the moral order really are self-evident, then God is justified in condemning all violations of them. Aquinas understood the importance of the issue: if natural law was to be an effective standard of justice accessible to all rational creatures, then it had to have been effectively promulgated (ST I-II.90.4. ad.1).Footnote 4
However, not only has the human will fallen but the whole mind has fallen. The problem is not just that we know what is good but do not do it; it is that we are confused as to what is good and as to what actions to take to pursue it.Footnote 5 This is the consequence of rejection of God described by Paul in Rom. 1:21–25, 28, 31. Aquinas recognises that people may be mistaken as to what is their ultimate good.Footnote 6 Modern sociological and anthropological research supports the conclusion that entire cultures may make fundamental misjudgments as to what is good.
Doubts about the self-evidence claim of natural law have become systematic. John Finnis and Germain Grisez have sought to defend natural law, but they claim self-evidence only for principles at a very high level of abstraction, requiring then a considerable amount of practical reasoning and or revelation in order to move from those principles to substantive moral decision-making.Footnote 7
It is key to the self-perception of Grisez and Finnis that they deny that an ‘ought’ can logically derived from an ‘is’.Footnote 8 They deny that their version of natural law, so-called New Natural Law, commits this naturalistic fallacy.Footnote 9 Instead, the move from theoretical reason about the ways things are to actions must be made by bringing practical reason to bear. Practical reason is about choosing how to act wisely in the face of the world which we understand by means of theoretical knowledge.Footnote 10
The New Natural Law claim is therefore merely a claim that the moral order is know-able, not that its contours are self-evident from a study of what is.Footnote 11 In theological terms this claim has two advantages. One is that it creates space within a natural law framework for revelation. Revelation is no longer unnecessary or a second-rate substitute for sound moral reasoning. It now illuminates and guides rational thought about the moral order. Revelation is thus restored to the place it arguably held in Aquinas' conception of the relationship between revelation and reason.Footnote 12 The second advantage is that, whilst the objectivity of the given moral order is preserved, God's judgement is just if it takes into account ‘the light available', the possibilities open to individuals in given societies. This makes sense of much of the attitude of the Old Testament to the surrounding nations.
However, this does not get over the second problem associated with natural law. The clearest, although not the only, New Testament support for the doctrine of natural law is to be found in Romans 1 and 2. There, however, it is to be found in conjunction with ‘natural theology’.Footnote 13 The wrath of God which ‘is being revealed from heaven against all the godlessness and wickedness of men who suppress the truth by their wickedness’ is just because ‘what may be known about God is plain to them, because God has made it plain to them. For since the creation of the world God's invisible qualities– his eternal power and divine nature –have been clearly seen, being understood from what has been made, so that men are without excuse. (Rom. 1:18–20). As Aquinas put it: ‘We do not know God by seeing his essence, but we know him from the order of the whole universe.’Footnote 14
The logic of the argument in Romans 1 appears to be as follows: God has created in a world in which creation reveals enough about the God who made it for human beings to be without excuse if they do not realise who God is and what God desires of them. Ignorance of God is no defence because the knowledge of God is mediated through God's creation; God wills to be known. As Jonathan Edwards put it: the evidence of God in the ‘contrivance of the world’ is sufficient to condemn humanity.Footnote 15
However, this aspect of Paul's thought causes difficulty for those, such as myself, who regard the Trinity as a touchstone of Christian faith. As Barth realised (and as Aquinas saw centuries before him) when he chose it as his starting point for his Church Dogmatics, the Trinity is a revealed doctrine par excellence and it goes to the heart of who God has shown Himself to be. While Judaism and Christianity share a common stock of moral values, and can find significant common ground with Islam, what divides Christianity from the other two Abrahamic faiths is its insistence on the deity of Christ and the revelation of the Trinity.
The danger with a natural theology is that, if you start with a natural theology and try to work upwards, you never arrive at a doctrine of the Trinity. Kant concluded that the Trinity was a doctrine he could make no sense of and could find no use for. Barth saw clearly what was at stake, he therefore started his theology with the Trinity and left no space for either natural theology or natural law.
The danger is a real one. Any approach to Christianity which majors on natural theology constitutes a ‘dumbing-down' of the faith. If everything important can be discerned by means of natural theology, then the Incarnation was unnecessary. Moreover, if all the important moral principles are given in natural revelation, Jesus’ teaching becomes at best an optional extra, at worst an unrealistic vision of a life which may only be pursued in the world to come.
The place of Romans 1 and 2 within the scope of Paul's argument in that letter is therefore of the utmost importance. N.T. Wright's assertion that Romans 1:1–4 set the tone for the letter is compelling.Footnote 16 The letter begins in thoroughly trinitarian fashion. Paul identifies himself as the herald of the Gospel about the Son of God who was raised to life by God the Father through the Holy Spirit. The chapters which follow are a demonstration that this event is good news for both Gentiles and Jews who were alike in need of a Saviour (Rom. 1:16–17; 2:1–3; 3:9–20, 23–24). The revelation of God and of His law given in creation does not have saving effect, because human beings do not live by the light revealed to them. Instead, justification is the free gift of God, achieved through the obedience and sacrificial death of His Son.
Moreover, Paul was not wrong to link natural law and natural theology. Michael Schluter has argued that relationships are foundational to the vision of society in the Mosaic law and that Jesus, by identifying the two great ‘Love’ commandments as the key to the rest, made this plain in his teaching. God's law, both revealed in the Law of Moses and given in creation, is not given as an end in itself, but as a guide to good relationships with Him and with other people.
As Oliver O'Donovan points out, failing to understand what God has revealed about Himself leads to misunderstanding what God requires of you, that is to say, it leads to a misunderstanding of the given moral order. On his account, ‘[k]nowledge of the moral order is a grasp of the total shape of things in which, if anything is lacking, everything is lacking.’Footnote 17 The resurrection-ascension of Jesus Christ is the keystone of moral reasoning, which both illuminates the moral order given in creation and highlights its transformation in the new creation which is to come and which has already begun.
The problem with the claim of O'Donovan that unless seen from the vantage point of the resurrection-ascension, human understanding of the moral order is inescapably muddled, is that it suggests that the moral order is unknowable even in part. Human beings who have rejected, or not yet come to accept Christ, cannot be justly criticised for their moral failures, because these are but the consequences of the fact that they do not see the moral order in its true light. The consequence of this is that human sinfulness becomes reducible to a rejection of the revelation of God-in-Christ. All manifestations of human sinfulness simply flow from this.
While it is undoubtedly right to locate the primary form of human sinfulness as the rejection of the revelation of God-in-Christ, Jesus taught that there were two Great Commandments. Human beings are guilty before God not just because we do not love God as we should but also because we have not loved our neighbour as ourselves. On the contrary, we are often guilty of treating people as things. Even if we see our moral obligations through necessarily distorted glasses, unless our ethical thinking is re-ordered through Christ, we know enough to condemn ourselves for our failure to act as we know we should. In the parable of the sheep and the goats, ‘the only norm that appears explicitly by which people will be judged is love of one's neighbour.’Footnote 18
While Aquinas would agree with O'Donovan that where Christ has been revealed, what is decisive is whether that revelation is accepted or rejected; he also holds that all human beings have the opportunity to decide whether to revere and fear God. That is the end for which we are made, and where that is not recognised, any other virtues human beings may display are radically defective.Footnote 19 Natural law, is, for Aquinas, part of a careful theological scheme designed to establish the responsibility of human beings for their own sinfulness and the grace of God who offers humankind salvation.
2. Recasting the debate
The English language debate about natural law and natural theology has become bogged down by terminology, in ways reminiscent of the debates regarding the meaning of righteousness in the New Testament. Oliver O’Donovan is so chary of the overloaded meaning of “natural law” that he tries to avoid using the term, although Novak is right to describe him as presenting ‘the most theological view possible of the doctrine of natural law.’Footnote 20
The revelation-reason dichotomy expresses the matter misleadingly, in so far as it suggests that natural law and natural theology are things which we find out by ourselves. If the word “natural” is replaced by the word “created”, then the created law is the law given by God in creation. A better way of expressing the dualism in human knowledge of God's moral order is in terms of general revelation and special revelation. Morality contains some aspects which God has revealed to human beings, whether or not they recognise the God who has revealed these things to them (general revelation). If we have knowledge of any truth, this is from the Holy Spirit who bestows the natural light of reason (ST I-II.109.1 ad.1). Morality also contains other aspects which can only be understood when the God who has revealed them is recognised (special revelation). To the former category corresponds general revelation; to the latter special revelation. Although I disagree with the terms in which he frames the discussion, Frank Mobbs draws out the point neatly:
… I can … believe the proposition contained in You shall not kill and thus believe what God says in the Decalogue, and not be believing God speaking in the Decalogue. For instance, I may never have heard of God or of the Decalogue, and yet believe the proposition.Footnote 21
Given what has been revealed in the light of natural law, and given what God has revealed of Himself through his creation, all human beings are answerable for their failure to give due worship to God and for their failure to treat others in accordance with the requirements of natural law revealed to them.
3. Re-thinking natural theology
It has been argued so far in this paper that Aquinas, like Paul, holds to doctrines of natural law and natural theology not in order to establish a means by which human beings can be accounted righteous apart from the saving work of Christ but rather in order to demonstrate the justice of God in condemning unrighteous human beings and His graciousness in saving them through Christ (ST I-II.91.5 ad.2).Footnote 22
Aquinas attributed a lot less to ‘natural theology’ than his detractors have claimed. In particular, he taught that while people might, through the exercise of natural reason, conclude that there is a god and that we owe obligations towards this god, the revelation that God has provided pardon for sin through the death of His Son is out of reach.Footnote 23 It is only given to those to whom God has revealed Himself to know that we can have assurance of forgiveness of sins.
Alongside the scholastic presentation of natural law in the Summa Theologiae, Aquinas also averts to natural theology in his commentary on the book of Hebrews. The position of these references in both works is significant. In the ST, natural law is referred to in a single question in the context of a broader discussion concerning the divine law, the old law and the new law. In the Commentary on Hebrews, Aquinas is expounding on a book whose central theme is the superiority and importance of Christ.
For Aquinas, the bare minimum of faith is expressed in Hebrews 11:6.Footnote 24 It consists of the belief that God exists and that he rewards those who earnestly seek him. This much has been revealed to all human beings. For Aquinas, the significance of this statement is that it comes in the list of the heroes of faith, the description of those who have been commended from the time of Abel. Thus God's faithfulness to some in all times of human history is described. However, the God who can be conceived by means of this natural theology can only be outlined in the sketchiest of terms. Hence Paul's observations in Athens that this God is essentially unknown (Acts 17:22–28).Footnote 25 However, the Triune God in His graciousness, forgives such ignorance where it is excusable because Christ has not been proclaimed (Acts 17:30).
With regard to the ST, Matthew Levering's book Christ's Fulfillment of Torah and Temple marks a major new departure in studies of Aquinas. As Stanley Hauerwas notes, one of its particular strengths is Levering's demonstration that ‘Aquinas’ understanding of the law, and in particular natural law, cannot be separated from his account of salvation.’ For Levering, central to Aquinas’ account of Law is not the natural law but the disclosure of God through the Old Law and the New Law.
As Levering expounds Aquinas’ scheme, the natural law may be in principle be known but human beings find it impossible to obey.Footnote 26 The Old Law (the Mosaic Law) was therefore given so that, through its moral precepts, the natural law might be clearly known (ST I-II.98.5 and I-II.100.1). The people of Israel continued to find its moral precepts impossible to obey (ST I-II.100.10 ad.3, ST I-II.91.5),Footnote 27 but the ceremonial precepts were given so that through their prefiguring of Christ's sacrifice the people might be acceptable to God.Footnote 28 Thus Israel was taught to hope for a Messiah ‘who would fulfill the written law, both in its literal commands and in its figurative significance’.Footnote 29 What is decisive in the New Law is that the knowledge of God's law is given inwardly and that the empowerment to obey it is given through the indwelling presence of the Holy Spirit.Footnote 30
However, although now is the age of grace, the operation of the New Law is not confined to the age of grace. The people of God were saved by faith, just as we are. As Aquinas puts it in ST I-II.98.2 ad.4 ‘Although the Law did not suffice to save man, yet another help besides the Law was available for man, viz., faith in the Mediator, by which the fathers of old were justified even as we are. Accordingly God did not fail man by giving him insufficient aids to salvation.’Footnote 31 In ST I-II.106.1 ad.3 Aquinas says ‘No man ever had the grace of the Holy Ghost except through faith in Christ either explicit or implicit: and by faith in Christ man belongs to the New Testament.’ For Aquinas therefore, salvation is, from the first point to the last point of human history, always by grace, through faith, in Christ.
Aquinas taught that in all times and places there have been people who believed, at least implicitly, in Christ. In places where biblical revelation was unknown, the essentials of this faith were a belief in Divine Providence, a trust ‘that God would deliver mankind in whatever way was pleasing to Him.’ (ST II.II.2.7.ad.3) Such belief was not a purely human phenomenon, but was a participation in the New Law, which is the grace of the Holy Spirit. It was a looking forward in faith to the Saviour.
This participation is proleptic, that is to say, it is, through the grace of God, an attribution by Him of the benefits of the saving work of Christ.Footnote 32 Precisely because Aquinas holds Christ to be the sole and universal mediator between God and humankind, so he sees the benefits of Christ's saving work as being potentially applicable to all people at all times and in all places. Precisely because he sees salvation as the work of the triune God, it is always the Holy Spirit who moves people to believe in God.
Because the Holy Spirit is the Spirit of Christ, where Christ has been revealed, it is He who must be believed in. In his Lectura in Matthaeum, Aquinas points to the Transfiguration as evidence that only those who hold to faith in the Trinity will enter heaven (Et quare tres tantum? Ad designandum, quod nulli pervenient nisi in fide Trinitatis) and supports this with reference to Mark 16:6, which Aquinas understands as teaching that salvation comes through faith [in the Trinity] and baptism [in the name of the Trinity].Footnote 33 In his commentary on Hebrews, he stresses that it is faith in the incarnate Son that is salvific (In Heb. 10.19–25 [502]).Footnote 34
So-called natural theology is, therefore, no substitute for faith in Jesus Christ. It is a vastly inferior form of knowledge of God. Nor is so-called natural theology sufficient for salvation. Salvation is to be found in Christ alone. Human beings cannot, by their own efforts, their own works or their own religious insight, put themselves in a position to make claims on God. However, God reserves to Himself the prerogative to save through Christ, if He so graciously chooses, people of all nations, tribes and tongues in all places and at all times in human history. Such people are brought to a measure of faith through the Holy Spirit. This is Aquinas' position.
4. Re-thinking natural law
The traditional conception of natural law seems to be vulnerable to two contemporary objections. One is that it is behaviourist. In other words, natural law appears to be concerned only with what people do rather than what people are. Second, it presents what is a deeply unfashionable picture of God as primarily a lawgiver.
As an alternative to behaviourism, Stanley Hauerwas, Alasdair MacIntyre and others have developed virtue ethics. As Hauerwas points out in his ethic of character, ‘living rightly is a matter of the whole person – of the self – not simply some element of the person, such as his conduct.’Footnote 35 Rufus Black in Christian Moral Realism argues that this approach has more in common with the natural law philosophy of Germain Grisez and John Finnis than might appear at first sight.
Another way of re-orienting natural law might be to re-think what it means to be righteous. Although the meanings to be ascribed to righteousness language in the New Testament remain highly contentious, there is a strong case to be made for saying that in the Old Testament at least the concept of tsedeqah is a relational term.
As Christopher Marshall rightly notes,
the Hebrew idea of righteousness is comprehensively relational. … Righteousness is, at heart, the fulfilment of the demands of a relationship whether this relationship is with other human beings or with God. For this reason, righteousness language frequently appears in covenant-making contexts, for “covenant” was Israel's term for a committed relationship. …
This applies pre-eminently to Israel's covenant with Yahweh. …Israel's righteousness consists in exhibiting the ethical and religious conduct specified in the terms of the covenant … Law, covenant, and righteousness are thus interpenetrating concepts. To be righteous is to be faithful to the law of the covenant-keeping God and thus to treat fellow members of the covenant community with justice.Footnote 36
Michael Schluter's own research into the biblical social vision led him to the same conclusion. When Jesus places the Two Great Love Commandments at the heart of the Law, He is confirming that right relationships with God and with our fellow human beings are at the heart of the moral order. Such was the purpose of the Torah: to show the people of God how to live in right relationships with one another and how to live in right relationship with God.Footnote 37 Conversely, to break the moral aspects of the Torah is to damage relationships. God's people's disobedience to Him is portrayed as adultery (Jer. 3:6–9; Ezek. 16:15–58; 23:35–49; Hos. 1:2; 4:15). It is a fundamental breach and rejection of their personal relationship with God.
If the Torah is fundamentally focussed on promoting good relationships, and if, as I have argued elsewhere,Footnote 38 the Torah sets out the moral principles of natural law, then it becomes possible to place natural law in relational perspective. A relational understanding of natural law need not be reductionist – reducing obligations to rules of behaviour. On the contrary, natural law can be understood as underscoring the fact that we are to love our neighbours as ourselves by reinforcing our obligations towards our neighbours.
5. Natural law and common grace
The existence of natural law is both a testimony to God's justice and to God's common grace. It is a testimony to God's justice in that God has made aspects of the moral order clear to all peoples, so that all shall be without excuse on the Day of Judgment. It is a testimony to God's common grace in that even where God's self-revelation in Jesus Christ is not recognised or is rejected, the moral order which coheres in Christ cannot be totally disregarded. It is a mystery of divine providence how, on the one hand, wholly vicious societies are prone to swift collapse whilst, on the other, societies which may display a high degree of violence and wickedness are sustained, sometimes over extended periods of time.
Grace is key to Aquinas' account of how natural law meets the criterion of promulgation which he has posited is essential for all law (ST I-II.90.1). Natural law is effectively promulgated because, [Aquinas] says, “God puts it into men's minds to be known naturally.” (ST I-II.90.4 ad.1). What Aquinas needed to go on and say was that the triune God puts the natural law into human minds by means of His Spirit. To have done so would have stressed the personal agency of the Spirit and therefore guarded against rationalist distortions of the idea of natural law.
Supplementing Aquinas' thought in this way explains why he teaches that the natural law was not lost entirely by any human community after the Fall, nor could it have been (ST I-II.94.6). For a community to be without revelation of the natural law would mean that there was a human community which was without grace and, given that our existence and its continuance is wholly dependent on divine grace, that is unthinkable.
6. Natural theology and common grace
Aquinas' account of implicit and explicit faith is carefully formulated so as to avoid making the former an adequate substitute for the latter. It is designed to account for the way in which the heroes of faith listed in Hebrews 11 and others are beneficiaries of the saving work of Christ. Aquinas would agree with O'Donovan, amongst others, that Christ is the indispensable sum of the revelation of God. Therefore, where Christ has been proclaimed, there is no question but that belief in Him is essential for salvation.
However, at the time before Christ appeared (and query in those places where Christ has not been proclaimed), express belief in Him is not possible and therefore God may graciously accept human beings whose faith sees less.Footnote 39 Nonetheless, for Thomas, ‘everyone in every age is bound explicitly to believe that God exists and exercises providence over human affairs.’ (de Ver. 14.11).
However, after the appearance of Christ, in the age of grace ‘both the leaders and the simple people are bound to have an explicit faith in Christ's mysteries.’ (ST II-II.2.7). Even here there is a graduation between what is to be expected of the leaders of the Church and of its ordinary members.
In the time of grace, everybody, the leaders and the ordinary people have to have explicit faith in the Trinity and in the Redeemer. However, only the leaders, and not the ordinary people are bound to believe explicitly all the matters of faith concerning the Trinity and the Redeemer. The ordinary people must, however, believe explicitly the general articles [of the Creed]… (de Ver. 14.11).
Mere belief in a god and in that god's providence is, therefore, for Aquinas, not an option where Christ has been proclaimed. For Aquinas natural theology does not render the Christian message optional speculation or traditioning of the revelation of the divine. On the contrary, it is an account of how the just God has revealed enough of Himself to all humankind to account them sinful in refusing to know what God has given of Himself to be known.
7. Conclusions
There is a place for natural law and natural theology in Christian thinking. However, they are essentially devices which serve a theodicy, an explanation of how God is righteous and gracious and why all human beings are sinful. Far from making salvation through Christ optional, properly understood they render it essential.
