Aquinas on the Metaphysics of Esse in Christ

The Thomist 66 (2002): 231-50 AQUINAS ON THE METAPHYSICS OF ESSE IN CHRIST J. L.A. WEST University ofWaterloo Waterloo, Ontario, Canada NE OF THE MORE controversial issues in Aquinas's Christology has been his position on Christ's esse. In a way this is not surprising, given the fact that the metaphysics of esse is one of the most discussed aspects of Aquinas's thought. Yet, the case of Christ brings with it an added difficulty due to the fact that St. Thomas held in many works that there is one esse in Christ,1 while arguing in one work, the Disputed Question on the Union ofthe Word Incarnate, that the human nature can be considered as having a secondary esse.2 1 The standard texts are: III Sent., d. 6, q. 2, a. 2; Quodl. 9, q. 2, a. 2 [a. 3]; Comp. Theo/. I, c. 212; and STh III, q. 17, a. 2. Throughout the paper I use the following abbreviations to refer to editions of Aquinas's works: (1) Q.D. De Anima, De Pot., and De Unione all refer to the texts included in Quaestiones Disputates, 2 vols., ed. P. Bazzi et al. (Turin: Marietri, 1949); (2) Sent.: In quatuor Libras Sententiarum in S. Thomae Aquinatis Opera Omnia, vol. 1, ed. Roberto Busa, S.J. (Stuttgart: Frommann-Holzboog, 1980); (3) STh: Summa Theologiae, ed. Petri Carmello, 3 vols. (Turin: Marietri, 1952); (4) ScG: Summa contra Gentiles, ed. Ceslai Pera et al., 3 vols. (Turin: Marietri, 1961); (5) Quo!.: Quaestiones de Quodlibet, ed. Commissio Leonina, vol. 25, 1and2 (Paris: Les Editions du Cerf, 1996); (6) In Boet. de Trin.: Super Boetium de Trinitate, ed. Commissio Leonina, vol. 50 (Paris: Les Editions du Cerf, 1992); (7) Comp. Theo!.: Compendium Theologiae in Opuscula, Ill, ed. Commissio Leonina, vol. 42 (Rome: Editori de san Tommaso, 1979); (8) De ente: De ente et essentia in Opuscula, Ned. Commissio Leonina, vol. 43 (Rome: Editori de san Tommaso, 1976). 2 There is no longer any doubt that the De Unione is authentic. There remains some question about whether it is to be dated as an early work or a late one, though the general consensus is that it was written shortly before Aquinas wrote the third part of the Summa Theologiae. While I am inclined to think it is earlier than this, no definitive resolution of this question will be possible until the critical edition of the text appears. A summary of the standard argument for a late dating can be found in Jean-Pierre Torrell, O.P., St. Thomas 231 232 J. L.A. WEST The aim of this article is twofold.3 The first is critical: I argue that there is no authentically Thomistic sense of esse that would allow Christ to have a second esse in virtue of his human nature without falling into one of the erroneous doctrines on the Incarnation, which St. Thomas is dearly trying to avoid. My second concern is to articulate and defend what I take to be the foundation of Aquinas's one-esse view, the doctrine that Christ's human nature enters into communion with the esse of the Word. I. THE THEOLOGICAL CONTEXT The theological framework within which the question of Christ's esse becomes a central issue is provided by Peter Lombard's presentation of three different schools of thought on the Incarnation.4 The first opinion, the assumptus-homo theory, held that the Word assumed a man. Thomas rejects this view as entailing the Nestorian doctrine that there are two persons in Christ.5 The second opinion, the one Thomas accepts, is the subsistence theory. On this view, the Word subsists in the human nature. Finally, the habitus theory argued that the Word took on the human nature in much the same way as a man puts on a doak. The doak-that is, the humanity-is transformed, while the person remains unchanged. Aquinas rejects this account as failing Aquinas, vol. 1, The Person and His Work, trans. Robert Royal (Washington, D.C.: The Catholic University of America Press, 1996), 205-7. 3 For detailed discussions of other issues relevant to Christ's esse see A. Patfoort, O...