Some thoughts on Aquinas’ teaching on the vice of infidelity, by John Hacker-Wright, from the Florida Philosophical Review, Vol VIII, Issue 1, Summer 2008:
For Aquinas, disbelief or infidelity can arise in two ways, one of which is not blameworthy. Anyone who has not heard the call cannot be held accountable for failing to respond. Disbelief as a vice is the willed disposition not to believe. In the case of vicious disbelief, the truth is presented to the intellect, but the will turns the mind away from the truth (10, 3). For Aquinas, the most fundamental disposition behind such a refusal to believe is, of course, pride. Among the seven deadly sins, pride is, as Sirach 10:15 has it, the origin of all sin, for it is the intention to excel above God. Since this attempt implies at least one false belief about the nature and value of creatures, it leads to inordinate desires for temporal goods, namely, those goods whereby I would excel above God (1a2ae 84, 2). Pride leads to contempt for God, whose greatness one wishes impossibly to surpass.
Now, blasphemy is associated with disbelief in that it consists of deliberately holding a false belief about God. The will and the intellect work together perversely in generating blasphemy. The will of the infidel who blasphemes is pridefully contemptuous of God. The infidel, because of this contempt, rejects the truth and embraces falsehoods about God. Even inwardly holding falsehoods about God is sufficient for blasphemy on Aquinas’ view (13, 1). Inwardly and intentionally forming a false proposition about God reveals a disbelieving disposition; it starts one on a course that, if continued, will render one utterly insensitive to truth, and thus, irretrievably separated from God. Blasphemy is therefore a major sin for Aquinas because it undermines an individual’s movement toward his chief end, the beatific vision. Of course, blasphemous thoughts that are published in any manner, whether through speech, writing, or artworks also perpetrate harm against others, on the assumption that the beatific vision is indeed their chief end and that their faith may be undermined in however small a way by the lies of the blasphemer.
In sum, for Aquinas, blasphemy is wrong because it is disorienting, both to the person who articulates it (whether inwardly or outwardly) and potentially to others who come into contact with the blasphemy. The disorientation works like this: I start with a true apprehension of God, including his ultimate value, but I begin to want things, temporal goods such as money. If I sinfully give in to such desires, I gradually want to become the richest and perhaps the most famous; these ideals affect my beliefs about what is good in life. My choices have affected my intellect by giving me a false view of what is good. I am now disoriented. Gradually, I am won over by an ideal that involves wanting to be the best, but in my own manner as a creature; that is, I cannot, as a creature, be the greatest in the way God is, but I can be the greatest creature, and I want that way of being the greatest to be the greatest, period. The will enters here to sway the intellect to disbelief. I want to believe, and choose to believe that God either does not exist or is not good in the way that he is presented in scriptures. I make him out to be susceptible to the flaws of creatures. I will no doubt want others to share my false view of God, which I may eventually come to believe, in order that they might at least come to share my inflated vision of myself. I have come to base my life on a false vision of what is good. My will and my beliefs are oriented toward a hollow, illusory, and indeed, an impossible goal, and I strive to bring others to share these views and desires in order to shore up my own moral mirage. I have, in this case, made of my life a worthless sham, through rejecting a genuine end, and, worse yet, I may not even realize it.