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

The Processions 63
we Wnd here that the intention to defend the faith furnished the opportunity
for the Fathers’ speculative meditation (our doctors). St Thomas conceives his
enquiry as an extension of patristic reXection.58 To disclose the divinity of the
Spirit and the kind of existence which belongs to him, it is necessary to show that
his procession is of a diVerent kind from that of the Son. And one cannot show
this on the basis of the concept of ‘generation’, simply because the procession
of the Spirit is not a generation. As he did with the Son, Thomas concentrates
his meditation on the notion of ‘immanent procession’. The explanations in
the Summa Theologiae are extremely concise:
Procession exists in God only according to an action which does not tend to anything
external, but remains in the agent himself. And, in an intellectual nature, such action
is that of the intellect, and of the will. The procession of the Word belongs to an act of
the intelligence. As to the operation of the will, for us it gives rise to a diVerent
procession which is that of love, whereby the object loved is in the lover (in the same
way that, by the procession of the word, the thing spoken or known is in the knower).
Hence, in addition to the procession of the Word, there exists in God another
procession which is the procession of Love.59
St Thomas is looking for an analogy which enables one to grasp the procession
of the Holy Spirit (without which one can assert it, but one cannot
disclose it!). To this end, he uses the analogy of spiritual life, which had
already worked well in conceiving the generation of the Son, this time
referring it to aVective action: volition belongs to intelligent beings.60 To
understand how he draws out the theme in Trinitarian theology, we must
consider Thomas’ original idea of love.
Thomas sets his presentation of aVective life within a metaphysics of action
that is governed by one fundamental principle: ‘every form gives rise to a
certain inclination which corresponds to it’.61 One can understand it like this.
A being is what it is through a ‘form’ which gives it being in this or that way,
for instance as a hazel tree, a piano, or a bat. This form is a principle of being
and it is also the principle of an inclination towards something, that is, the
principle of an action. For example, a case of a substantial form, a dog barks,
eats bones, engenders other dogs, and so forth by virtue of its dog-form: the
form which speciWes its dog-being entails inclinations corresponding to that
form, inclining the dog to certain acts which Wt what it is. Thomas distinguishes
on this basis three types of form, which are the source of three sorts of
‘appetites’ (appetitus) or inclinations of a being towards that which conforms
58 The question about the Holy Spirit’s proceeding without being begotten is central to
Augustine’s thinking: see De Trinitate I.V.8; II.III.5; IX.XII.17–18; XV.XXV.45; XV.XXVI.47;
XV.XXVII.48; XV.XXVII.50.
59 ST I, q. 27, a. 3. 60 SCG IV, ch. 19 (no. 3558). 61 ST I, q. 80, a. 1.