We have another, more reliable source from which to learn: the sacred liturgy. In the pre-Conciliar liturgy, when only major feasts enjoyed the right of a proper Preface, the usual Preface for most Masses was that of the Holy Trinity. In this way, the central dogma of the faith was constantly linked to the Eucharistic celebration. Bernard Lonergan, SJ, never tired of pointing out this connection when lecturing on the Trinity, and he finds in the Preface of the Trinity a precise theological formulation clearly rooted in the landmark determination of the Nicene Fathers, St. Athanasius in particular.
What homoousious meant exactly, was formed by Athanasius thus: eadem de Filio quae de Patre dicuntur, excepto Patris nomine. The same meaning has been expressed in the Trinitarian Preface: Quod enim de tua gloria, revelante te, credimus, hoc de Filio tuo, hoc de Spiritu Sancto sine differentia discretionis sentimus. Now such a determination of meaning is characteristically Hellenic. It is a matter of reflection on propositions. It explains the word “consubstantial” by second-level proposition to the effect that the Son is consubstantial with the Father, if and only if what is true of the Father is also true of the Son, except that only the Father is Father.
Lonergan, “The Dehellenization of Dogma” in A Second Collection, pg. 23. It is also found in as a reference (footnote #13) in “Consciousness and the Trinity” in Philosophical and Theological Papers, pg. 129. [my emphasis in bold]
Further in the Preface, we find: “…in Personis proprietas, et in essentia unitas...” Thus we come to the landmark intellectual achievement of the post-Apostolic and Patristic era, in which both the Platonic hermeneutic of form and matter, and the Aristotelian substance-accident duality, gave way to an innovative and indelible development in Christian thought. The philosophical concepts of essence and person, discovered only as a result of Christian reflection, bequeathed to the Church our classic formula for the Trinity: Una essentia, tres Personas.Essence and Personhood refer to two different forms of being. Essence is “what” a thing is– what Thomas Aquinas would later call quidditas. Without essence/quidditas, a thing ceases to be what it was. Essence gives identity– this concept is simple enough.
Far more complex is the idea of Person. In the grammatical development of European languages in the Modern era, the word “person” has come to denote an individual human being. This trend mirrors the drift towards subjectivism and individualism since the Reformation. This idea of “person”, however, is far removed from the original philosophical concept of “personhood”. In illo tempore, individual humans were always denoted as “man”, “woman”, “child”, etc. Without digging too deeply into the history of this term “person”, from its roots in ancient Greek drama, to prosopographic exegesis in Greek literary theory, to its application Scriptural interpretation beginning with Justin Martyr, to its transference to Latin thought in the word persona, we can say that the word “person” fundamentally denotes a relation. Relation is a fundamental aspect of being; a thing cannot “be” if it is not in relation to a context, a world, another “person” who can apprehend it. Think of films and plays: when an actor takes on the persona of his character, he adopts the manner in which his character relates to other characters, to the story, to the audience, and to himself.
Relation, or Personhood, fundamentally falls into three types: “being for”, “being from”, and “being with”. Each implies the other and each are inseparable in one essence. “Being for” denotes the creative, providential aspect of being. It signifies the ability to give and provide. “Being from” is simply the other side of that coin– the fact of receiving from another. “Being with” is the corollary which “proceeds” from the previous two. The reciprocal complementarity between “being for” and “being from” is a third relation in itself.
Man, if he lives to his full potential, simultaneously finds the three relations as inseparable in his own essence. He is a “being from” inasmuch as he has received life from another (proximately from his parents, remotely from God); he is a “being for” inasmuch as he participates in the generation of life and fosters its growth; he is a “being with” inasmuch as he is capable in uniting himself with another in a love so profound that it generates new life.
Thus, man is truly made ad imaginem Dei, for in him is the image of the Trinity. What philosophers described as “being for”, “being from”, and “being with”, Christian theologians have identified with Father, Son, and Spirit. The first is the Unbegotten, the second is the Only-Begotten, and the third is the unconditional love between the two. In Dante’s terms, we have la divina podestate, la somma sapienza, e ‘l primo amore. When we speak of the three Persons of the Trinity, we speak of the relationships within God himself and the relationship of God to the world. This mutual indwelling and inseparability of relations in the one divine Essence is what we mean when we confess the Holy and Undivided Trinity.
Relation or Personhood is not an accident added onto an essence; rather, relations bring the essence to full completion. Thus, in the Preface of the Trinity, we find: non in unius singularitate personae, sed in unius Trinitate substantiae. Back in the mid-1960’s, after a thorough study of Patristic texts, Joseph Ratzinger found that “the relatio stands beside the substance in an equally primordial form of being” (here he uses the term “substance” instead of “essence”, characteristic of his love for Tertullian and Augustine, though in this context they mean the same thing). Perhaps the distinction between essence and relation in the Trinity can be explained using the following schema
Non creatus, non factus, sed generans (Father)
Non creatus, non factus, non generans, sed genitus (Son)
Non creatus, non factus, non generans, non genitus, sed procedens (Spirit)
All three Persons have one thing in common: neither are created nor made. On account of their supreme power and divinity, as the first cause of all things, the three Persons must be one in essence. As to what they are, they are all God. They differ in the way they relate to one another: the Father begets, the Son is begotten, and the Spirit proceeds from the two.
Of course, not all this information is practical for a Sunday homily. But to distill the difference between essence and personhood can go a long way in clarifying the doctrine of the Trinity better than an appeal to a shamrock, for when the modern Catholic hears the word “person”, he/she automatically thinks of an individual human subject. The beautifully profound concept of personhood as relation, bequeathed to the world by Christian theology, needs to be recovered from the modern slide toward radical individualism. If recovered, more Catholics might have a greater appreciation for the image of the Trinity within them, and thus be brought up into its mysterious power.