In much modern christology, the notion of the incommensurate governs the relation of divine to human in Jesus Christ. In christologies influenced by Austin Farrer, and more distantly, by Nicholas of Cusa, the incommensurability of the infinite to the finite makes the idiom of paradox congenial, even necessary. Such demanding and unrelenting emphasis upon diastasis echoes a more ancient preoccupation with holiness in a fallen and unholy world. In Israel's scriptures, and in their lasting influence in the patristic era, the transcendent holiness of God threatens to prohibit the presence of the Holy One in the midst of unholy people. A record of this threat can be seen in the alien, fragmentary and unrecognisable Gospel portraits of the holy Christ to a sinful world. Yet the doctrine of the incarnation demands a divine presence to sinners and a sinful cosmos, a ‘making flesh’ as well as an ‘assuming flesh’. The concept and practice of sacrifice is proposed as a form of relation between deity and humanity such that the holy Christ can dwell and abide in an unholy world.

This article argues that Summa Theologiae 3a Q17 art. 2 is consistent with the attribution of a proper being to Christ's human nature. It proceeds in three stages. First, it examines the emergence of the problem of Christ's being through an analysis of the Chalcedonian Decree. In so doing it argues that the decree commits its adherents to accepting that Christ's human nature was an individual nature and it shows how Aquinas used his account of natures and essences to interpret this. Second, it considers five objections to the view which denies a proper being to Christ's human nature. Third, it argues that Christ's individual human nature can possess a proper being because (i) esse does not render an individual nature a person and (ii) the character and function of the divine esse entails that it could not receive any new esse from the individual human nature Christ possesses.

For over 700 years scholastic theologians of varying degrees of allegiance to the text(s) of Thomas Aquinas have discoursed on the mystery of Christ's being (esse): Did Christ have one or two acts of existence? Yet despite this frequent and recurring quaestio, nevertheless only a handful of scholastic commentators pause to note that this is not simply a debate between rival scholastic ‘schools’ in regard to a theological mystery, but that in fact there is an inconsistency within the Angelic doctor's own texts. And while in more recent scholarship this discrepancy has not only been noticed but explicated in various ways, nevertheless it is the contention of this paper that a satisfactory exposition of the meaning of esse secundarium has not yet been achieved. Consequently, I propose in this paper that esse secundarium is the created, substantial, but absolutely supernatural participation of the human nature of Jesus in the uncreated communication of the divine esse of the Word and provide a robust textual defense of this interpretation.

The claim that article four of Thomas Aquinas’s De unione verbi incarnati is a reversal of his consistently held single esse position is challenged in this paper. The article argues that reading all five articles of the De unione as a single-structured argument discloses a single esse understanding of the Incarnate Word. The very nature of the radically hypostatic union between God and man in Christ is at stake in this dispute. According to Thomas, positing a second esse in Christ not only contradicts the tradition, especially of the Christian East, that he appropriates, but it would also compromise the reality of the hypostatic union itself.