In his Breviloquium, Bonaventure (1221-1274), the great medieval Franciscan theologian and Doctor Seraphicus (“The Seraphic Doctor”), offers a succinct description of the doctrine of the Holy Trinity. The parts in brackets I have added for the sake of clarity. This excerpt is from Part I, Chapter 3:
PART I, CHAPTER 3 – ON THE RIGHT UNDERSTANDING OF THIS FAITH
- Sacred doctrine contributes to the right understanding of this faith by teaching that there are, within the Godhead, two modes of emanation, three hypostases, four relations, and five concepts; and yet in all only three personal properties.
- This should be understood as follows. The first and supreme Principle [i.e. the Triune God], by the very fact that He is first, is utterly simple; by the very fact that He is supreme, is utterly perfect. Being utterly perfect, He communicates Himself with complete perfection; being utterly simple, He remains completely undivided. Therefore, within the first Principle there are modes of perfect emanation which leave oneness of nature unimpaired. But the modes of perfect emanation are only two, through nature and through will; the first is generation [i.e. the Father generates the Son and the Son is generated by the Father], the second spiration-procession [the Spirit is spirated (breathed-out) by the Father and the Son and proceeds from the Father and the Son].Hence these are the two modes found here.
- Now, while two hypostases [i.e. the Son and the Spirit] necessarily result from two substance-producing modes of emanation, we must also posit that the original producing hypostasis [i.e. the Father] does not itself emanate from anything else, for then we should have an infinite series. Hence there are here THREE HYPOSTASES.
- Again, because each mode of emanation implies a twofold relation, there are here FOUR RELATIONS: paternity and filiation [between the Father and the Son]; spiration and procession [the Father and the Son spirate or breath out the Spirit, while the Spirit proceeds from the Father and the Son].
- By such relations, the divine hypostases are made known to us. But the original producing hypostasis [i.e. the Father] is shown to have no originator, which is the very reason for its characteristic excellence. Hence there are here FIVE CONCEPTS: the four relations indicated above, and unbegottenness.
- Furthermore, each Person enjoys one property through which He principally is made known. Hence there are here but THREE PERSONAL PROPERTIES, characteristically and principally indicated by the names: Father, Son, and Holy Spirit.
- The Father is properly the One without an originator, the Unbegotten One; the Principle who proceeds from no other; the Father as such. Therefore, UNBEGOTTEN ONE designates Him by a negation, but also affirmatively through inference, since it implies existence within the Father of fullness at its source. PRINCIPLE WHO PROCEEDS FROM NO OTHER designates Him by an affirmation followed by a negation. FATHER designates Him in a proper, complete, and determinate manner by affirmation and the positing of a relation.
- The Son is properly the Image, the Word, and the Son as such. Likewise, therefore, IMAGE designates Him as the expressed likeness, WORD as the expressing likeness, and SON as the personal likeness. Again, IMAGE designates Him as the likeness in the order of form, WORD as the likeness in the order of reason, and SON as the likeness in the order of nature.
- The Holy Spirit is properly the Gift, the mutual Bond or Love, and the Holy Spirit as such. In the same way, then, GIFT designates Him as the One who is given through the will; BOND or LOVE, as the One given through the will who is the Gift par excellence; and HOLY SPIRIT, as the One given through the will, the Gift par excellence, who is a Person.
Hence, the three names, Father, Son, and Holy Spirit, convey the personal properties of the three Persons.
This is what we must hold if we would rightly understand faith in the Holy Trinity.