The first harvest yielded by the theory of subsistent relations is the disclosure of an authentic plurality and alterity within the Triune God. St Thomas begins by exhibiting the plurality of persons professed by Christian faith. The theme of plurality within unity has nothing to do with any kind of mathematical hypothesizing or hermetic speculation on the meaning of numbers. Thomas explains it with the utmost clarity in his Questions De potentia:
the plurality of persons in God is an article of faith, and natural human reason is unable to investigate and adequately understand it... The holy Fathers, however, were compelled to discuss this and other matters of faith by the objections raised by those who denied the faith. . . . Nor is such a discussion useless, since it enables the mind to get enough of a glimpse of the truth to steer clear of error.3
1 The term 'monotheism' was unknown to the medievals. It only emerged in the seventeenth century (cf. R. Hulsewiesche, 'Monotheismus', in Historiches Worterbuch der Philosophie, vol. 6, ed. J. Ritter and K. Grander, Basel and Stuttgart, 1984, cols. 142-146).
2 See the prologues to questions 29, 30, 31, and 39.
3 De potentia, q. 9, a. 5; this observation echoes an analogous comment by St Albert on the same question (Albert, I Sent. d. 23, a. 3). See above, in Chapter 2, 'Understanding the Faith'.
Faith acknowledges that God is Father, Son, and Holy Spirit. Theology seeks to disclose the truth of this credal confession, by showing how and why we can truly say that the Father, Son, and Holy Spirit are 'three persons'. It is faith, and not a rationalization deriving simply from human reasoning, which leads to this affirmation.4 Theological investigation envisages its task as avoiding the dead-ends of Arianism and Sabellianism, in a exercise in contemplation whose fruits are passed on to believers. Standing on this ground, the exposition puts the study of relation and person to work, with precision:
From what we have said it follows that there are several persons in God. For it was shown above that 'person' used of God means relation as a reality which subsists in the divine nature. It was also established that in God there are several real relations. Hence it follows that there are several subsisting realities in the divine nature. And this is to say that there are several persons in God.5
One can easily see that this response is the upshot of question 29 ('relation as a reality which subsists') and also of the ideas which Thomas drew out of the study of relation in question 28 (it gave him 'several real relations'). What interests Thomas in these discusses is plurality. The recognition of a plurality of real subsistent relations enables one to show how we can understand the plurality of persons in God. And, by giving us a plurality of persons, it gives thinking believers the chance of seeing why the language of faith can accurately use the word 'persons' in the plural. This plurality is not a matter of three 'absolute' entities within God (which would undermine the simplicity and unity of God, by colluding with tritheism). The issue is one of a 'plurality of relations' in God, leaving the unity of the divine nature intact, since the being of the relation is the being of the nature.6
As he formulates it in his synthesizing works, this response is less banal than one might be led to suspect. Albert, for instance, had been content with fine-tuning the Patristics' discourse on Trinitarian plurality, and exhibiting specimens of it,7 reminding people that the distinction of the persons derives from the relative properties.8 Following the lead of Alexander of Hales, whose Summa likewise calls on the relations,9 and refining the traditional terminology, St Bonaventure looked to the fruitfulness in the Trinity (the fact that goodness, charity, primacy, and perfection require a plurality of persons) to bring about plurality amongst the persons.i° But none of these authors
4 See above, in Chapter 2, 'The Rejection of Rationalism'.
5 ST I, q. 30, a. 1; cf. De potentia, q. 9, a. 5. 6 ST I, q. 30, a. 1, ad 3.
7 Albert, I Sent. d. 23, aa. 3-7. 8 Albert, I Sent. d. 23, a. 8; cf. d. 2, a. 9.
9 Summa fratris Alexandri, Book I (ed. Quaracchi, vol. 1, nos. 314-316).
10 Bonaventure, I Sent. d. 2, art. 1, q. 2 and q. 4.
presents a response comparable to Thomas'.11 The comparison of their responses with the one Thomas gave in his Commentary on the Sentences also shows the development of his thinking on the topic. In his 'Writing on the Sentences', he explained perfectly well that the name person signifies relation as subsisting, but he does not turn to the notion of relation when he needs to account for the use of the word persons in the plural.12 The notion of subsistent relation appears in a more developed form in the De potentia, where Thomas' main concern is to validate his theory of the Word.13 The Summas response to this question is a benchmark.
From this same position, 14 Thomas can show why there are neither more nor less but three persons in God. It can be surprising that he raises this as a problem, since the confession of three persons rests on the Church's received revelation alone. So one can ask if speculative reason is applicable here. When he poses this question, Thomas is pursuing the same goal as in the preceding question. It is not a matter of proving the Trinitarian faith by an intellectual contrivance. Rather, the theologian seeks to disclose the clarity of the mystery to the minds of believers, that is, to give an account of the Church's profession of faith in three persons, not limiting himself to arguments from authority found in the Councils or the Fathers, but taking the light of faith into those avenues which reason offers us for grasping a little piece of the truth of this profession. This question also creates the opportunity for testing the mettle of the idea of processions, relations, and persons, letting it prove itself. We can briefly look at these features.
(1) So far as the persons are concerned, it has been shown that to say 'many persons' is the same as saying 'many subsistent relations', each of which is really distinct. Here one takes up the bearings which q. 29 has on the person, and also the results of q. 28, where Thomas showed that relations of origin which are 'opposed' are really distinct from one another.
(2) On the topic of the relations, the real distinction is derived from relative opposition, as q. 28 established. And there are four opposed relations; this has also been established earlier. These relations constitute relatively opposed pairs: paternity and filiation, and spiration and procession. As opposed, paternity and filiation are linked to two really distinct persons; and as subsisting, they are these persons: 'subsisting Fatherhood is the person of the Father, and subsisting Sonship is the person of the Son'.15 As we have
11 Bonaventure, I Sent. d. 23, a. 2, qq. 1-3. There are three persons in God, but not three substances (unless we take 'substance' to mean 'hypostasis'), nor three essences, nor three gods.
12 Thomas, I Sent. d. 23, q. 1, a. 4. u De potentia, q. 9, a. 5. 14 ST I, q. 30, a. 2. 15 Ibid.
already indicated on the topic of relative opposition, spiration is not opposed either to Fatherhood or to filiation; the fact of being Father and the fact of breathing the Spirit do not set up a differentiation of two persons within the Father! So it remains the case that, because of the relative opposition between spiration and procession, and because of the 'origin order' of Word and Love, procession is due to a third person who is really distinct from the Father and the Son: procession 'must belong to another person who is called the ''Holy Spirit'' '.16 The personhood of the Father, Son, and Holy Spirit must not be sought either beyond or prior to these relations of paternity, filiation, and procession. These three relations enable one to disclose three persons, neither more nor less. In combination with the theory of subsistent relations, in a meditation which makes use of its rigorous internal coherence, relative opposition also shows the divine tri-personhood, as taught by Scripture. It is not enough to say the persons 'have' these relations. One must also acknowledge that they 'are' the relations. One can see very clearly the consequences of the theory of subsistent relations.
(3) Finally, in relation to the processions, Thomas comes back to the distinction between the generation of the Son and the spiration of the Holy Spirit in the terms posited by q. 27. The one is the procession of the Word as through the intellect, and the other has the mode of Love. As we have seen, these two are the only immanent processions that can be reasonably grasped in God, by means of an action that founds a real relation. This prohibits the conflation of procession with Fatherhood or filiation.17
As one considers them, each of the building-blocks of this meditation, such as subsistent relation and especially the idea of the Word and of Love, puts Thomas' own way of presenting Trinitarian faith to work. Even though the other Masters posed exactly the same question, it is not astonishing that their thought should follow different paths.18 One can also notice the progress Thomas achieved after his 'Writing on the Sentences'. On the same question, of why three persons in one God, our author was still thinking in terms of 'natural-mode' or 'voluntative-mode' processions, without also clearly making use of the theory of subsistent relations.19 The issue of the number of the persons is perhaps not a central question in the treatise, but it does highlight the theological resources which Thomas is now able to put at the heart of his theological doctrine.
17 ST I, q. 30, a. 2, sol., ad 3 and ad 4; cf. q. 27, aa. 3 and 5. See above, in Chapter 4, 'The Cycle of the Trinitarian Processions'.
1® The most proximate exposition is doubtless Albert's: I Sent. d. 10, a. 12.
Was this article helpful?