As we celebrate the feast of the Holy Trinity, I can’t help but admit that a triune God is beyond my comprehension. As a child, I was taught that I had to rely on faith to accept the fact that there are three persons in one God. As an adult, I am still dependent on that faith; however, I turn to various writers and theologians to help me further process the Trinity’s mystery.
St. Thomas Aquinas, for one, has given me greater insight into the Trinity. In trying to explain the unity, plurality, and equality of the three persons he stated, “paternity is the person of the Father, filiation is the person of the Son, procession is the person of the Holy Spirit proceeding.” Aquinas likewise said, “We do not say absolutely that the Son alone is Most High; but that He alone is Most High with the Holy Spirit, in the glory of God the Father.” The persons work “with” and “in” each other, as one God.
The terms “procession” and “proceeding” which I have heard all my life, provide new insight as I explore trinitarian teaching. I now realize that in making the Sign of the Cross, saying prayers, and singing songs in church, I was continually proclaiming – and consequently internalizing a belief in – the triune God, regardless of my ability to truly understand it. Furthermore, I now realize that the three persons invite me to participate in their union.
Aquinas highlighted the fact that if the Father, Son, and Holy Spirit existed exclusively for themselves in their own community, there would be no need for this “procession,” except in relationship from one person to the other. Additionally, since “procession” is a noun indicating something “done” or limited, in including the verb “processing,” Aquinas points to the fact that the Trinity is not fixed, but active. The Trinity is an engaging union into which humanity is called.
In their book An Introduction to the Trinity, Declan Marmion and Rik Van Nieuwenhove also provide insight into the Trinity’s invitation to us. They state that “the triune God is no longer viewed along the lines of [an] … absolute subject, but rather as a network of relationships inclusive of humanity,” and enhance their explanation of the Trinity with a photo of Andrei Rublev’s icon entitled The Hospitality of Abraham.
This icon, based on Genesis 18:1-5 when three men visited Abraham, displays three figures seated around three sides of a rectangular table. The table’s fourth side, in the forefront, remains vacant as if they are awaiting someone. Presuming this fourth place is for us, the painting provides a visual image of the three members of the Trinity inviting humanity to share in their union. God revealed himself to Abraham as a representative of Israel, and the icon reminds us that the Trinity continues as an enduring “circle of love,” calling us into the mystery of “triune harmony.”
The Trinity’s harmony, extended to humanity, is revealed most clearly in Jesus’ life, death, and resurrection. Marmion and Van Nieuwenhove explain that God desires our salvation – and eternal union with him – “otherwise [the Trinity] wouldn’t have been revealed.” The Trinity reveals this plan for salvation, designed out of love by the Father, accepted and enacted out of love by the Son, and continued in the ongoing, loving actions of the Holy Spirit.
While each of these explanations helps me to articulate, visualize, and even respond to the relationship of the Trinity, its mystery remains beyond my comprehension. Jesus walked the earth to meet humanity in tangible and identifiable ways to lead us to our heavenly home. Responding to his example and his teachings is perhaps the best place to begin responding to the Trinity’s invitation to us.
Even though I cannot fully understand the Trinity’s union, I feel its call. I recognize the fatherly presence of the Creator; I appreciate the brotherly example and selfless sacrifice of the Son; I sense the Spirit moving in my heart and in this world.
In faith, each person prompts me to pull up a chair at the Trinity’s table and humbly respond – in the name of the Father, the Son, and the Holy Spirit - to the greatest invitation ever extended.