Chapter 4 discusses Thomas’s account of original guilt. Infants are guilty only in an analogical sense. A human being with the use of reason is guilty in the proper sense when she commits a sinful act of her own volition; an infant is guilty in an analogical sense when she fails to receive original justice by Adam’s volition. The infant is in a moral middle ground, between the state of mortal sin and sanctifying grace (Scriptum II, d. 35, q. 2, a. 2, ad 2). She has not turned away from God, yet she needs grace nonetheless. Thomas’s explanation of infant guilt developed. He initially compared the guilt of original sin to an inherited disease (Scriptum II, d. 30, q. 1, a. 2). He later abandons this analogy and compares the infant to a homicidal hand. I defend Thomas’s view that the infant’s will is positioned between mortal sin and sanctifying grace. But I criticize his view of analogical guilt, arguing that receiving the effect of another’s sinful act cannot increase one’s own guilt.

Chapter 5 engages proposals that deny the importance of a historical Fall. I begin with Kant’s account of radical evil. An influential reading is this. Every human being who reaches the age of reason freely subordinates the moral law to self-interest. Next is Karl Barth’s “christologized” version of radical evil: the Fall is the universal act of unbelief in Christ. I argue that the reduction of original sin to the universality of actual sin is insufficiently inclusive. Neither infants nor the severely mentally disabled choose wrongdoing. Schleiermacher separated original sin from the Fall in a different way. Original sin is the corporate act of humanity. The “force” of sin is present in infants, albeit in germinal form, and when they mature they lack God-consciousness and tend to sinful self-love. Schleiermacher’s view leads to a problematic conclusion. Either sin is numerically one, or sin is merely environmental, external to the will. Schoonenberg defends a similar view but stresses human freedom. McFarland intriguingly proposes a synthesis of Maximus’s and Augustine’s accounts of the fallen will, while arguing that we can avoid etiological explanations of sin altogether. I argue, however, that we have to choose: we need either to explain why original justice is theologically unnecessary or to defend it in some form.

Chapter 1 puts Thomas’s account in its historical context by discussing Augustine and his medieval reception. The first part of the chapter focuses on Augustine’s mature account of original sin, drawing on The City of God and his anti-Pelagian works. I argue that Augustine’s account contained several fruitful ambiguities which would be the basis for medieval reflection. How should we understand the transmission of original sin and the origin of the soul? In what sense are infants guilty of sin? How can we make sense of the claim that human nature has been “corrupted”? The second major part of the chapter discusses Anselm of Canterbury, Peter Abelard, and Peter Lombard. Each of these theologians defended original sin while challenging at least one important aspect of Augustine’s teaching. Anselm claimed that concupiscence cannot be sinful. Abelard denied original guilt. The Lombard emphatically denied traducianism and insisted that infants who die unbaptized are guilty only in a highly mitigated sense.

Chapter 2 argues that Thomas’s mature view of the formal cause of original justice created an unresolved problem for his doctrine of original sin. Though his early writings sharply distinguished the rectitude of the human will in the state of original justice from supernatural sanctifying grace, by the mid-1260s (e.g., STh I, q. 95, a. 1) he implied that the formal cause of original justice is sanctifying grace. The problem is that Thomas also held (1) that Adam should have been the principal cause of original justice in his posterity and (2) that no creature can be the principal cause of sanctifying grace. Thomas’s mature view implies that the disposition to original justice never could have been sexually transmitted. This implies that his account of original sin as a whole needed to be modified. Adam’s failure to transmit the disposition to original justice rendered the lack of original justice sinful in his posterity: if Adam couldn’t have done this in the first place, how could his descendants have original sin?

Chapter 8 responds to potential objections. Against the objection that my proposal is a recrudescence of “two-tier Thomism,” I argue that it is deeply congruous with Henri de Lubac’s view that nature innately desires grace. The second objection is that my view implies that a state of pure nature is impossible. I argue that it is in fact compatible with a wide variety of views of divine providence. Further objections are raised that focus on the nature of sanctifying grace, the ecumenical potential of a Thomist perspective, and Pelagianism. My proposal, I suggest, is compatible with a wide variety of views of justification, and it is not “Pelagian” in any meaningful sense.

Chapter 3 argues that Thomas radically reconfigures the relation between original sin and human nature. Whereas Augustine had argued that nature is “corrupted” by the Fall, Thomas draws on Denys the Areopagite to argue that strictly speaking, human nature survives the Fall. For Thomas, there are two senses of the word “nature.” In the strict sense, “nature” refers to the principia naturae and the propria that follow therefrom. The secondary sense of “nature” refers to what is good for nature – including communion with God. Thomas regularly uses Augustinian language concerning the corruption of nature by sin (e.g., STh I–II, q. 109), but when he explains this usage he indicates that it is improper (e.g., De malo q. 5, a. 2). Nature is “corrupted” only insofar as human beings have lost the good of nature, original justice. The principles and properties of human nature – including the orientation to God – remain. This is why Thomas argues that children who die unbaptized will know and love God in limbo.

Chapter 7 proposes a new Thomist view of original sin. The core of Thomas’s proposal – that original sin has more to do with the lack of a right relation to the Triune God than the inheritance of personal guilt or corruption – is defensible today. His mature teaching stressing the necessity of supernatural grace for original justice, however, implies that he should have denied that original sin has a necessary connection to Adam’s failure to sexually transmit justice. I propose a “new Thomist view,” on which original sin is the lack of sanctifying grace. Grace is the Father’s gift of the Holy Spirit that orients the person to Jesus Christ. Every infant is born with human nature but called to exist in Christ. I construct this account in dialogue with biblical scholarship and respond to the challenges posed by evolution. I sketch two possible views of the Fall compatible with the new Thomist view of original sin.

Chapter 6 unpacks salient hypotheses in contemporary evolutionary theory that challenge traditional views of the Fall and original sin. The first challenge comes from the gradual nature of evolutionary change. On the modern synthesis of Mendel’s account of particulate inheritance with Darwin’s account of natural selection, evolutionary change happens gradually. It is hard to see how a single volition could have corrupted human nature. (This seems to be true even on the “extended evolutionary synthesis.”) The second challenge, or rather set of challenges, stems from the legacy of our evolutionary history. It appears that at least some human beings were disposed to sinful forms of behavior (e.g., aggressive violence), and yet at the same time we have evolved dispositions to altruistic cooperation. This causes problem for the traditional Augustinian account of both pre- and postlapsarian human nature: human desires seem not to have been perfectly ordered before the Fall, and after the Fall it seems that we aren’t entirely selfish. The third challenge stems from the widely supported hypothesis that the human population never dipped below 6,000 individuals. Either some people were created in sin or far more people were created without sin than traditionally assumed.

Many people today believe that the doctrine of original sin is pernicious, antibiblical, irrational, and opposed to the deliverances of the scientific community. A significant number of Christians share at least some of these concerns or objections, while at the same time believing that the doctrine is part of their faith. In constructive and critical dialogue with the most important accounts of original sin in the history of theology, this book has sought to respond to these concerns (focusing on those raised by evolution). Here I review the major arguments of the book and suggest a few directions for future research.

What gave rise to this superstition? Who taught Tess that children who die unbaptized are damned? Surely no reasonable religion would teach that children are condemned simply because they weren’t sprinkled with water. If we had put this objection to Tess or her priest, however, a response would have been ready to hand: “in every person born into this world, it deserveth God’s wrath and damnation.”2 The Church teaches that every child deserves damnation. Innocent in the eyes of the world, Sorrow was guilty in the eyes of God: he had contracted “original sin” in his mother’s womb.