St. Thomas Aquinas, the renowned thirteenth-century Dominican biblical commentator, theologian, and philosopher, considered the object of theological knowledge to be God and all things in relation to him. To appreciate the profundity of this perspective, we must set aside contemporary misconceptions which reduce knowledge to the acquisition of data, the biochemistry of neural networks, or the interpretations we construct to give meaning to our experiences. By knowledge, Aquinas has in mind an encounter with reality that engages and transforms a human person. In keeping with the broad outlines of Jewish and Christian experience, and adapting (not simply adopting) approaches developed in Greek philosophy, he viewed the act of knowing as a type of personal union with the perceived object. The heart of this approach is perhaps best captured by the biblical use of the verb to know in reference to the personal encounter by which husband and wife become one (see Gen 4:1; Luke1:34). Knowledge, then, is not information we extract from reality or a meaning we construct or impose. Rather, it is an encounter that unites us to someone or something and, in so doing, inwardly shapes (that is, “in-forms”) not only our minds but who we are as persons. In this relationship we gain insight into the known object and ourselves, which then enables us better to understand and interact with others and the world around us. Ultimately, St. Thomas is saying that theology is rooted in a personal encounter with God which unites us to him and, in him, to all creation in a manner that transforms us so we can live in a proper relation to them. That union takes place in Jesus of Nazareth as members of his Body and Bride, the church.

In order for our considerations of God and his Eternal Covenant to be fruitful, we must continually be aware we are engaging in a personal encounter with God in Christ that is meant to lead us to a deeper appreciation for and participation in his works of creation and salvation. We are not neutral investigators attempting to subject God and his ways to analysis, as if we were gathering data for clinical study. The knowledge we seek, while capable of being intellectually expressed and analyzed, is fundamentally a matter of personal participation, of engaging and entering the reality we desire to know. This is what the Christian tradition means when it speaks of theological mysteries, such as the mystery of the Trinity, the mystery of the Incarnation, and the Paschal Mystery of our salvation in Christ. These are not puzzles that challenge and inevitably surpass human comprehension; they are interpersonal realities whose meaning can be understood and appreciated—yet never fully grasped—only by being immersed in them. If we forget this basic truth, we cannot avoid distorting theological knowledge into the abstract or idiosyncratic speculations of our own minds. While we might find such distorted “knowledge” comforting or compelling in certain ways, it originates in us, not in God, and therefore cannot unite us (or others)to him.

There is another aspect of knowledge we must recognize before proceeding. Because knowledge is based in a type of personal union and participation, it is distinct but not separable from our capacities for love and generous self-commitment. Love is the innate attraction we have as persons (rooted in the spiritual capacity of the will) which arises in response to whatever is good and seeks the satisfaction of being united to that good. In this primary sense, love is not a matter of free choice or emotion but is a foundation from which those can arise. Free choice is our responsible and uncoerced selection of a particular good from the many which, being good, naturally attract and satisfy us (a child, on the other hand, responds to goods without responsibility). The attraction and satisfaction of love arising in the will can “overflow,” as it were, in a manner that affects our bodily emotions and, in turn, can be influenced by those emotions. (In extreme situations bodily senses and emotions can overwhelm the will so that our responsibility is mitigated or negated.)

In knowing and loving someone or something, we are engaged in an encounter that invites us, indeed, summons us, to affirm and commit to whatever is true and good and to denounce and reject whatever is false and evil. The activity of the mind (or intellect) is thus entwined with the activity of the heart (or will) and together they engage the depths of the human person (or subject) as he generously commits himself. Yet, while these three activities are profoundly personal, they arise in response to and are authenticated by the reality of the object. Knowledge, love, and commitment, then, are “subjective” human actions whose authenticity is measured “objectively” and relationally. Note that this is the opposite of both the neutral objectivity advocated in Enlightenment thinking and the autonomous subjectivity of postmodernity. In short, we should be deeply, subjectively engaged with others and the world, but as they are objectively rather than as we imagine them to be through false ideas or narratives.

The affirmations or negations we make, such as “Two plus two equals four,” “You are good,” “That is false,“I love you,” and “I hate that,” express a personal act engaging our mind and heart by which we take a particular stance in relation to God, others, and the world, thus committing ourselves by uniting or separating ourselves from them in various ways. These subjective commitments shape (but do not entirely define) who we become as persons, and they are objectively either sound or unsound. When undertaken with knowledge and free choice, they are morally either good or evil. For these reasons, the love of God with an attendant reverential fear of betraying him and his love is considered by Jews and Christians to be the beginning of wisdom and morality. This belief harmonizes with the assessment of many Greek and Roman thinkers who held that human formation and education begin by instilling a love for what is good and a hatred for what is evil. In order for us to be united to God, then, our knowledge must not only come from him, it must also be rooted in a love that comes from him.

This vision of knowledge and love as enabling generous, committed relationships to God, others, and the world which form us as persons is essential for our discussion of the Holy Trinity, the Eternal Covenant, and all that follows in later chapters. This perspective will hopefully deepen and expand as we proceed. For now, it should encourage us to approach these mysteries prayerfully and contemplatively, opening our heart and mind so that we might not merely analyze the words we read or the thoughts we ponder, but seek to encounter the reality which informs them. That is the goal of all theology and, more importantly, of life itself. We find eloquent witness to this truth not only in the insights Aquinas left us but also in the man himself. It is reported that Jesus once said to him: “Thomas, you have written well of me. What reward do you wish?” The saint replied with a wisdom born of love, “Nothing except you, O Lord.” Afterward, Aquinas ceased writing. Six months later he died.