The Difference Divine Mercy Makes in Aquinas’s Exegesis

IN THEIR ESSAY, “Mercy in Aquinas: Help from the Commentatorial Tradition,”¹ Romanus Cessario and Cajetan Cuddy have masterfully performed the task of presenting the rich and voluminous commentatorial tradition on Aquinas, distilled into central philosophical and theological themes. In particular they identify the “real distinction between act and potency (form and matter)” as “the key philosophical principle” that created the “essential unity of their theological project.” This principle expresses the fundamental distinction between God and creation. Yet the prominence of this philosophical principle in Aquinas and his commentators raises a question: To what extent can a philosophical principle be prior to a theological project?² Would not it be more faithful to the witness of Scripture and the creeds to begin with revealed theological principles and then adopt philosophical principles that fit within that theological worldview?

This way of approaching the problem reveals both a profound misunderstanding and a profound concern. First, nervousness over philosophical principles reveals a profound misunderstanding since human beings always remain within language and the world and thus the meaning of that language and its references to the world around us must necessarily be part of the reception and transmission of divine revelation. To avoid philosophical principles would be tantamount to adopting a philosophical principle of pluralism or eclecticism.³ Second, there is a legitimate concern that some philosophical principles or understandings of God and human beings could constrain the newness of divine revelation along the lines of a rationalistic deism as was attempted by Locke and others. This concern also takes the form of the desire to bring theology back to its central relationship with sacred Scripture, with the concern that a philosophically determined theological hermeneutics would distance theology from the world of biblical revelation.

Aquinas’s presentation of theology, or sacra doctrina, as a scientia helps here by distinguishing between philosophical truths about God and human beings and philosophical principles by which human beings receive theological truths about God and human beings.⁴ Aquinas shows that the principles of the scientia of sacra doctrina are taken properly from divine revelation received by the faith.⁵ Thus, the principled understandings of God and the human creature come from revelation, not from natural reason or philosophy, by which only a few could come to know some truths, after a long time, with an admixture of error.⁶ Nonetheless, the human creature cannot but receive this revelation as true. As Aquinas says, the virtue of faith attains to God as the prima veritas. The judgment that something is true and not false presupposes the application of philosophical principles about the nature of the human intellect and the nature of the intelligibility of that which the intellect apprehends. The key philosophical principles here would be, first, the principle of non-contradiction and, second, the real distinction between act and potency. The first is necessary for the human intellect to reach a true judgment; the second is necessary for that judgment to be a trustworthy judgment about a constantly changing world.⁷ By making this distinction between philosophical truths about God and human beings and philosophical principles by which human beings receive theological truths about God and human beings, the Thomistic tradition avoids the deistic rationalism that occludes the biblical revelation.

Even if philosophical principles are necessary for the human reception of revelation, there remains the concern that emphasizing the philosophically laden superstructure of the theological project obscures or weakens the ability of the theological project to attend to the biblical witness and the existential situation of human beings. To address this concern, I want to examine Aquinas’s own practice of biblical interpretation as it applies to questions of God’s mercy. This examination will also consider how the philosophical principle of the distinction between God and his creation, highlighted by Cessario and Cuddy, illumines the biblical revelation. I will examine three occasions on which Aquinas speaks about mercy in its biblical context: first, his commentary on Ephesians 2:4, which describes God as “rich in mercy”; second, his commentary on Matthew 5:7, which speaks of “Blessed are the...