The Trinitarian Theology of Saint Thomas Aquinas - El Camino ...

14 Revelation of the Trinity
and to the Spirit’s subsisting as a person. Even though Scripture does not
directly ascribe the name God to the Holy Spirit—as it does to the Son—
Thomas’ biblical reading here is like his practice of exegesis in relation to the
Son. Once again we Wnd the soteriological argument which Thomas developed
in relation to the Son, this time for the Holy Spirit. The divinity of
the Holy Spirit sets the scene for one of Thomas’ best formulations of the
soteriological argument:
It is clear that the Holy Spirit is God, since he says, unless one is born again of water and
the Holy Spirit, he cannot enter the kingdom of God....From this we can form the
following argument: He from whom men are spiritually reborn is God; but men are
spiritually reborn through the Holy Spirit . . . therefore, the Holy Spirit is God.33
St Thomas presents this reXection as an argument (ratio) which believers,
working from scriptural teaching, can use their reason to formulate. The divine
action of the Holy Spirit manifests the Spirit’s divinity. In the same way, the
unity of action of the Holy Spirit and of Christ discloses their consubstantiality:
although his action has a diVerent modality, the Spirit does not accomplish
something diVerent from what Christ does; thus, his nature, the principle of
his action, is not diVerent from that of the Son of God.34 When Thomas
approaches the subject in this way, he is drawing out the legacy of the fourthcentury
Church Fathers.35 On this issue, one can look at many chapters in the
Summa Contra Gentiles which focus on the patristic exegesis springing from the
anti-pneumatological controversy (the Pneumatomachai, or‘Wghters against
the Spirit’).36 Thomas presents the works of the Holy Spirit in detail. This is a
matter of works which God alone can perform, so the witness of Scripture
induces one to acknowledge the divinity of the Spirit: the Holy Spirit creates,
gives life to the dead, observes, instructs and inhabits human hearts, brings
about justice, receives divine glory, speaks through the prophets, reveals the
mysteries of God, and is the source of sanctiWcation (one can hear the echoes of
the Creed of Constantinople). This is one example of Thomas’ soteriological
reXection, chosen from amongst many:
33 In Ioan. 3.5 (no. 444).
34 In Ioan. 14.15 (no. 1912). On the strict parallelism of the actions of the Spirit and of Christ
in St John and St Paul, see especially Yves Congar, I Believe in the Holy Spirit, vol. 1: The Holy
Spirit in the ‘Economy’, trans. David Smith, London, 1983, pp. 55–59 and 84–86; cf. Congar, The
Word and the Spirit, trans. David Smith, San Francisco, 1986. On Thomas’ idea of the mutual
work of the Son and Spirit, see the beautiful collection of texts, brought together, translated and
annotated by L. Somme: Thomas d’Aquin: La divinisation dans le Christ, Geneva, 1988.
35 For instance, Athanasius of Alexandria explains: ‘If [the Holy Spirit] divinizes, there is no
doubt that his nature is that of God’ (Letter to Serapion I.24; SC 15, p. 126); cf. Letter to Serapion
I.23; I.27; I.29 (SC 15, pp. 124, 132, 135). Basil of Caesarea mines the same vein (see especially
Basil, Letter 159, in Lettres, ed. and trans. Y. Courtonne, in SC 17, 2nd edn, pp. 132–133).
36 SCG IV, chs. 15–17.