In this expanded version of his Cambridge dissertation, Lombardo follows a path blazed by G. Aulén; he commends a retrieval of the devil's ransom interpretation dominant in the patristic period while subjecting both Anselm of Canterbury and Peter Abelard to critique. The approach Lombardo takes is original, suggestive, and provocative. In seven chapters he constructs the criteria he believes any soteriology must meet. The first criterion is negative: it must not involve God in moral evil. The other two are positive: a soteriology must honor Jesus' historical attitude, whereby he both expected his death and regarded it as advancing his objectives, and it must also honor the New Testament conviction that the Crucifixion was a necessary component of God's plan of salvation. Three final chapters then apply these criteria. Lombardo finds that Anselm fails to shield God from willing moral evil, Abelard falls short on the necessity of the Crucifixion, and the devil's ransom, carefully interpreted, fulfills all three criteria.

Central to Lombardo's first criterion is the validity of double-effect reasoning. To establish this point Lombardo works through linguistic analysis and phenomenology toward a contemporary version of natural law ethics in the Thomist tradition. This construct serves in turn as a grammar for considering the relation of God's will to Christ's crucifixion. For his second criterion he appeals to the genre of the gospels as ancient biography to establish that they in fact make historical claims, and he validates as historical the claim that Christ prophetically foresaw his fate and found positive significance in it from the fact that that claim permeates the gospels, whose testimony can be trusted—by a free decision—for various reasons. Thirdly, the New Testament offers a wealth of texts asserting that Christ's crucifixion is an ontological constituent of the divine plan of salvation.

Lombardo focuses his reading of the Cur Deus Homo on chapters 8 to 10 in book 1, where Anselm seeks to obviate God's apparent injustice in willing the death of his innocent Son. Lombardo finds the argument of these chapters “tortuous, confusing, and maddening” (162) and unsuccessful. Yet, granting the inadequacy that Lombardo unearths, it need not taint Anselm's work as a whole. The key to Anselm's concept of satisfaction is that it be something supererogatory, so that an application of Lombardo's double-effect reasoning would exonerate Anselm from the charge of involving God in moral evil. In addition, a close reading of Anselm's work might reveal that the necessity he claims for the death of Christ in fact amounts to what Aquinas will call convenientia, the intelligibility of the contingent matter of fact. This observation in turn raises the question of the status of Lombardo's third criterion, by which he finds Abelard wanting. In what, precisely, does the necessity that Scripture attributes to Jesus' death consist? Lombardo informs his reader that the necessity is not absolute but salvific, and this qualification opens the way to a rapprochement of Lombardo's biblical necessity with the convenientia within which Aquinas situates Abelard's insight.

Turning to the metaphor of the devil's ransom, Lombardo offers an original, richly textured study of its biblical origins and the “family of interpretations” within which it functioned—devil's rights, God's deception of the devil, Christ's harrowing of hell—and finds the hermeneutical key to this complex in the sign of Jonah, dominant in early Christian art and a trope that links Christ's death and resurrection to baptism. It was Anselm, and not the Fathers, who literalized this metaphorical material in his critique of devil's rights, and the ransom metaphor unlocks the soteriological import of Christ's good shepherd saying: Christ provokes evil and draws it upon himself, only to overcome it in his resurrection. Lombardo intends this book for his peers, and it is well worth their engagement.