Three in one: believing in the triune God

Christian Century, April 17, 2007 by William C. Placher

TO UNDERSTAND something complicated, we often begin with something similar yet simpler. The analogous ease gives us a start in the process of understanding, although, to be sure, later on we have to do some deconstructing, discovering how the two eases are different as well as similar. With respect to the triune God, the theological tradition offers two analogies--one social, one psychological--that give hints at insight even while reminding us that all analogies break down well before we reach real understanding of God.

Scripture tells us that human beings are made in God's "image and likeness" (Gen. 1:27-28), so human beings are an obvious place to start in looking for analogies for God. Two obvious features of human beings are 1) that we exist in relation with others and 2) that we think and consciously pursue goals. In Aristotle's famous terms, humans are at once "political animals" and "rational animals." A person would not be human, Aristotle says, if he did not exist in relation to other humans, as part of a community. A person would also not be human if he did not engage in acts of knowing and willing--and at the core of willing is to desire or love something. From these two characteristics of humanity, theologians developed a "social analogy" and a "psychological analogy" to the Trinity.

The "social analogy" has been common in trinitarian thinking in the Eastern church and appeared also in the West, particularly in the work of Richard of St. Victor in the 12th century and Bonaventure in the 13th. God, Richard said, is love, and love needs an object: "As long as anyone loves no one else as much as he loves himself, that private love which he has for himself shows clearly that he has not yet reached the supreme level of charity." But, he observed, it would be disorderly for God to love anything in creation supremely, for created things are not supremely good. "Therefore, so that fullness of charity might have a place in that true Divinity, it is necessary that a divine person not lack a relationship with an equally worthy person, who is, for this reason, divine."

Two persons locked in mutual love, however, have about them a kind of selfishness that manifests an imperfection in their love. So, Richard concluded, "Nothing is rarer or more magnificent than to wish that another be loved equally by the one whom you love supremely and by whom you are supremely loved.... So a person proves that he is not perfect in charity if he cannot yet take pleasure in sharing this excellent joy.... Thus you see how the perfection of charity requires a Trinity of persons, without which it is wholly unable to subsist in the integrity of its fullness."

A difference arises between the human ease and the divine case. In the ease of human persons, each has a different body and thus a different spatial location. Further, they can disagree with one another and thus find themselves at odds, or they can turn inward on themselves and attempt to deny their essential relatedness. The divine three, however, are not embodied, are always perfectly in accord, and always glorify one another in mutual love, so that they are inseparably one even while they are three.

In contrast to this, Augustine proposed a psychological analogy, which was further developed by Anselm and Aquinas. The human mind, this analogy begins, exists in knowing and loving. But knowing and loving are not activities in which the mind happens to engage; rather, the mind exists precisely in the doing of these activities. Further, a person cannot truly love some thing without knowing that thing (or one would be loving only a figment one's own imagination), and cannot truly know something without loving it (for one needs the empathy of love to achieve full understanding): "And so you have a certain image of the Trinity: the mind itself and its knowledge, which is its offspring and its word about itself, and love as the third element, and these three are one."

Aquinas developed this analogy in more detail. Consider a mind engaged in knowing itself. In order to know itself, it has to form a concept--an image or likeness--of itself, what Aquinas calls "a word of the mind." If it knows itself perfectly, then that word will be an exact likeness of the mind that knows. In this ease, furthermore, the word is brought forth by the mind and has the same substance as the mind; and when one thing brings forth another that has the same substance as the first, we call that "generation" or "begetting." Hence the second element in the psychological analogy can be called not only the "word" of the first but also "begotten," "child"--or, in a masculine-oriented way of looking at such things, "son."

Loving, however, is different from knowing. The will does not create a likeness of that which it wills but rather has an inclination to the thing it wills. While perfect love involves knowing what one loves, it is the knowledge rather than the love that creates the image of the object known and loved in the mind. "So," Aquinas explains, "what proceeds in God by way of love, does not proceed as begotten, or as son, but proceeds rather as spirit; which name expresses a certain vital movement and impulse."