The most significant early medieval discussion of the concept of iustitia most appropriate to characterise God’s dealings with humanity is due to Anselm of Canterbury. It must be pointed out that Anselm’s soteriology has frequently been criticised as ‘legalist’, typical of the Latin ‘impulse to carry religion into the legal sphere’. This misguided and discredited criticism of Anselm, however, brings us to the very point which confronted Anselm as he began his attempt to defend the rationality of the incarnation of the Son of God: what was the relationship between the ‘righteousness of God’ and the ideas of ‘righteousness’ taken from ‘ordinary human life’?

God is wholly and supremely just. How can he then give eternal life to one who deserves eternal death? How can he justify the sinner? This is the central question with which Anselm is concerned in Cur Deus homo (1098). Earlier, Anselm had wrestled with substantially the same problem in the Proslogion (1079). Initially, Anselm locates the source of God’s mercy in the divine goodness (bonitas), which may be contrasted with God’s justice (iustitia). He then proceeds to argue, however, that despite the apparent contradiction, God’s mercy (misericordia) must somehow be grounded in God’s justice.

Anselm resolves this dilemma by arguing that God is just, not because God rewards humans according to their merit, but because God does what is appropriate to God, considered as the highest good (summum bonum). Although Anselm does not identify Cicero at this point, there is no doubt that he is mounting an explicit criticism of the Ciceronian definition of iustitia as reddens unicuique quod suum est at this point. Far from endorsing prevailing secular accounts of justice, as some less perceptive critics suggested, Anselm aims to disconnect the theological discussion of redemption from preconceived human patterns of distributive or retributive justice.

A similar pattern of engagement and criticism with secular concepts of justice may be seen in Cur Deus homo, where Anselm notes various interpretations of the concept of iustitia, before selecting that which is most appropriate for his purposes. These concepts include iustitia hominis, which pertains under law; iustitia districta, beyond which ‘nothing more strict can be imagined’ – Anselm presumably therefore understands iustitia hominis as iustitia aequitatis – and supreme justice, summa iustitia.

The concept of justice which Anselm selects as most appropriate to characterize God’s dealings with humankind is, as in the Proslogion, justice understood as action directed towards the highest good. As that highest good includes the redemption of fallen humankind, its salvation may be regarded as an act of divine justice. In the course of the discussion, however, it becomes clear that Anselm understands the concept of rectitude to underlie that of iustitia, and to determine its basic meaning.

According to Anselm, justice is a ‘rectitude of will served for its own sake’ (rectitudo voluntatis propter se servata). Similarly, truth must also be defined in terms of metaphysical rectitude. It will thus be clear that the foundational notion for Anselm is rectitude, which is understood to have metaphysical dimensions (truth – i.e., the conforming of the mind to what it ought to be) and moral dimensions (justice – i.e., the conforming of behaviour to what it ought to be.)

Anselm clearly assumes that the three concepts are closely linked, noting the intersection of their meanings. The concepts of ‘truth’ and ‘righteousness’ had, of course, long been recognised to have close conceptual connections, and Anselm may be regarded as establishing the conceptual foundation of both to be ‘rectitude’. Iustitia has as its fundamental sense the moral rectitude of the created order, established by God at creation, and in itself reflecting the divine will and nature. This moral ordering of the universe extends to the relationship between humans and God, and humans and their fellows. Anselm appears to use the term rectitudo to describe the basic God-given ordering of the universe, and employs the term iustitia in a number of derivative senses, each of which may be traced back to the fundamental concept of rectitude. God’s moral governing of the universe clearly involves both the divine regulation of the affairs of humans, and also the self-imposed regulation of God’s dealings with human dealings. For Anselm, it is not possible to argue that the laws governing each are the same. In its fundamental sense, iustitia merely refers to rectitude; it remains to be seen what form this ordering may take with respect to the various aspects of creation. Thus, the justice which regulates the affairs of humans (e.g., the Ciceronian and Justinian principle of reddens unicuique quod suum est) cannot be considered to be identical with the justice which regulates God’s dealings with humanity.

Humanity was created in a state of iustitia originalis, which was forfeited t the Fall. Anselm understands ‘original justice’ to refer to the initial moral rectitude of humanity within the created order. For Anselm, the basic requirement of iustitia is that rational creatures be subject to God, which merely amounts to a statement of the place of humanity in the hierarchical moral ordering of creation. This moral ordering of creation, itself an expression of the divine will, allots a specific place to humans, with a concomitant obligation that they submit their rational nature to God. This moral ordering of the universe was violated by humans at the Fall, so that the present state of humanity is that of iniustitia, understood as the privation of iustitia rather than as a positive entity in itself. The essence of original sin is the inherited lack of moral rectitude in the will of fallen humankind. The human violation of the moral order of creation means that they are no longer capable of submitting their rational nature to God – and therefore that they are incapable of redeeming themselves. If humanity is to be redeemed, a divine act of redemption is required which must itself be consonant with the established moral order of the universe. God, having created the moral order of the universe as an expression of his nature and will, is unable to violate it himself in the redemption of humankind.

This important point is made with particular clarity at that point in Cur Deus homo at which Anselm considers the question of why God cannot simply forgive sins as an act of mercy. For Anselm, God’s freedom in will and action is limited by God’s own nature; anything that violates this nature necessarily involves contradiction. Thus what is iustum cannot become iniustum simply because God wills it, as such an alteration would involves a radical change in the divine nature itself. God’s character as summa iustitia is expressed in the moral order of creation, and the free forgiveness of sins through mercy alone would violate this ordering. God’s attributes are essential to his being, and not mere accidents which God may change at will. Anselm’s fundamental theological insight is that the divine attributes must coexist within the limiting conditions which they impose upon each other. The rectitude of the established moral order thus requires that God redeem humankind in such a way that God’s own nature as summa iustitia is not contradicted.

In a very brief, but highly significant, review of the accounts traditionally given of the redemption of humankind in Christ, Anselm makes it clear that he is not satisfied with their failure to explain why God chose to redeem humans – at best, they were merely descriptions of how God redeemed them, so offering no explanation of why God should choose to redeem humans in the first place, or of the particular mode of redemption selected. Anselm therefore presents an account of the redemption of humankind, based on iustitia, which demonstrates

1. that the redemption of humankind is necessary as a matter of justice,

2. that this redemption is effected in a manner that is consonant with the divinely established moral ordering of the universe.

We shall consider these points individually.

If iustitia Dei is understood as a lex talionis, or in the Ciceronian sense of reddens unicuique quod suum est, it is clearly impossible, in Anselm’s view, to consider God’s act of redemption as an act of justice. It is for this reason that Anselm does not employ these concepts of justice in his soteriology. For Anselm, the moral ordering of the universe was violated by the sin of humans, so that the present state of affairs is that of a privation of justice – that is, iniustitia. As whatever is unjust is a contradiction of the divine nature, it is therefore imperative that the moral rectitude of the created order be restored. God, as summa iustitia, is therefore obliged, by his very nature (since to permit a state of injustice to continue indefinitely is tantamount to a contradiction of his nature) to restore the rectitude of the created order by redeeming fallen humankind – as an act of justice.

Anselm prefaces his discussion of the method by which God redeemed humankind by considering the rival theory of the ius diaboli, the ‘devil’s rights’. This theory may be illustrated from the tract De redemptione humana, attributed to Bede, in which it is argued that, while the death of Christ is a free act of divine love, the choice of the means employed to effect the deliverance of humanity from the devil is necessarily dictated by the fact that the devil is justly entitled to punish sinners. The origins of this teaching may be traced back to Gregory the Great, who taught that the devil had acquired a legal right over sinners as a consequence of the Fall, but had no such right over anyone who was sinless. Christ therefore assumed the form of a man in order to deceive his opponent, who naturally assumed that he, like the rest of humanity, was a sinner. As the devil thus brought about the crucifixion of the sinless Christ contrary to justice, his own legitimate power over sinners was justly abolished.

This theory admittedly makes an appeal to justice – but it is a concept of justice very different from that approved and employed by Anselm.

For Anselm, justice relates to the moral ordering of creation, to which the devil himself, as a rational creature, is subject. The devil clearly violated this order in his seduction of humanity, and thus cannot be regarded as having any just claim over humans. Himself a rational creature, the devil is obliged to submit his rational nature to God – only if he were not part of God’s creation, and could therefore stand aloof from its moral ordering, could the devil claim any ‘right’ over humanity. By his own violation of iustitia, the devil had lost any claim to ius over humans. Anselm therefore dismisses the theory of the work of Christ which had been current for so long, and with it, an unacceptable concept of iustitia Dei: ‘I do not see what force it has’ (non video quam vim habeat).

Anselm’s own theory may be stated as a series of propositions, if the numerous digressions are ignored. When this is one, the centrality of the concept of iustitia to his argument becomes apparent:

1. Humans were created in a state of original justice for eternal felicity.

2. This felicity requires the perfect and voluntary submission of the human will to God – that is, iustitia.

3. On account of sin, the present state of humanity is that of iniustitia.

4. Either this must result in the deprivation of eternal felicity, or else the situation must be rectified by an appropriate satisfaction.

5. This satisfaction must exceed the act of disobedience.

6. Humans cannot offer to God anything other than the demands of iustitia, and, on account of their present iniustitia, they cannot even do that.

7. Therefore God’s purpose in creating humans has been frustrated.

8. But this is unjust, and poses a contradiction to the divine nature.

9. Therefore a means of redemption must exist if justice is to be re-established.

10. Humans cannot redeem themselves, being unable to make the necessary satisfaction for sin.

11. God could make the necessary satisfaction.

12. Since only God can, and only humans ought to, make the necessary satisfaction, it must be made by someone who is both God and human.

13. Therefore the incarnation is required as an act of justice.

The importance of justice at this stage in the argument is often overlooked. The ‘syllogism’ – Aristotle, it must be recalled, had yet to be rediscovered! – which demonstrates the ‘necessity’ of the incarnation may be stated thus:

A. Only humans ought to make satisfaction for sin; but they cannot.

B. Only God can make the necessary satisfaction; but God is under no obligation to do so.

It is clear that this primitive ‘syllogism’ could lead to two conclusions.

1. Someone who is both divine and human both cannot and ought not to make such a satisfaction.

2. Someone who is both divine and human both can and ought to make such a satisfaction.

From a purely dialectical standpoint, the work in question could equally well be entitled Cur Deus non homo. However, as justice demands that humanity’s predicament be resolved, Anselm feels himself justified in drawing the second conclusion, and overlooking the first.

The weak point in Anselm’s soteriology is generally considered to be his theory of satisfaction, which we do not propose to discuss further. The essential point, however, is that Anselm considers, presumably on the basis of the established satisfaction-merit model of the penitential system of the contemporary church, that the payment of a satisfaction by the God-human would be regarded by his readers as an acceptable means of satisfying the demands of moral rectitude without violating the moral order of creation. For our purposes, this aspect of Anselm’s soteriology is subsidiary, the main element being his development of iustitia Dei as action directed towards the highest good, and thus embracing the redemption of humankind. Anselm’s soteriology is dominated by the understanding of justice as moral rectitude, and it marks a decisive turning point in the medieval discussion of the ‘righteousness of God’.

The theory that the devil has rights over humanity, which God was obliged to respect, continued to influence theologians for some time after Anselm’s death. Thus the school of Laon, marked by its extreme theological conservatism, taught that the devil had gained just possession of humanity because humanity had freely enslaved itself to the devil as a consequence of its sin. God is therefore obliged to respect the ius diaboli. The theological justification provided for the incarnation by the school of Laon is that it is only God who has the ability, and only humans who have the obligation, to overcome the devil; by logic similar to that employed by Anselm of Canterbury, the necessity of the incarnation is then deduced. The devil has no ius over the God-human, and by his abuse of his legitimate power, the devil forfeits his ius over humanity.

More or less every aspect of Anselm’s position was subjected to a penetrating theological critique by Peter Abelard. While in no way denying that the devil exercised potestas over humanity de facto, Abelard insisted that this power was not acquired or administered de iure. By seducing humankind, the devil acquired no rights over humans. If the devil has any power over sinful humanity, he possesses it solely by divine permission, in that God has allotted him the specific and delimited function of captor of sinful humanity in the economy of salvation. Within this circumscribed realm, the devil operates only subject to divine permission, not by his own rights; outside that realm, the devil has no rights whatsoever over humankind. As the devil does not possess even this limited potestas by an absolute right, God is at liberty to withdraw it. A similar position is adopted by Hugh of St Victor, who argues that although humankind is justly punished by the devil, his dominion over it is held unjustly. The school of Abelard, as might be expected, upheld its master’s teaching that the devil had potestas over humankind de facto but not de iure. Bernard of Clairvaux, an opponent of Abelard on so many matters, concedes that the devil’s power over humans may be said to be just in that it derives from God, but unjust in that it was usurped by the devil. The classic position characteristic of the later twelfth century is summarised in the teaching of Peter of Poitiers: the devil has no right to punish humans, but on account of their sin, humans deserve to be placed under his power.

The significance of this critique of the ius diaboli lies in the concept of iustitia employed to characterise God’s dealings with the devil. If iustitia is understood to entail the respect of established ius – that is, the situation as it exists de facto – then God is obliged to respect the dominion of the devil over humankind. If iustitia is instead conceived primarily as conformity to the divine will, the devil has no de iure rights over humans, having abused the limited and conditional rights which some theologians were prepared to allow him in the context of the economy of salvation. The general rejection of the ius diaboli by the theologians of the twelfth century is therefore of considerable significance in the development of the articulation of the ‘righteousness of God’.