The importance of the Reformation is on full display when one compares the thought of Thomas Aquinas with John Calvin’s on the topic of spiritual equality. Aquinas believed in an enduring spiritual inequality, one based on the limits according to each person’s nature. Grace “perfects” nature, but only to the extent of each person’s given nature. So in a state of perfection, some are more perfect than others. Calvin, on the other hand, held to an equality in the spiritual kingdom of Christ. Each person is justified by faith alone, and this justification has nothing to do with any natural capacity. Below I show the relevant texts.
All texts cited below are from Summa Theologica
In I.12.6, Aquinas asks “Whether of those who see the essence of God, one sees more perfectly than another?” He answers in the affirmative.
I answer that, Of those who see the essence of God, one sees Him more perfectly than another. This, indeed, does not take place as if one had a more perfect similitude of God than another, since that vision will not spring from any similitude; but it will take place because one intellect will have a greater power or faculty to see God than another. The faculty of seeing God, however, does not belong to the created intellect naturally, but is given to it by the light of glory, which establishes the intellect in a kind of “deiformity,” as appears from what is said above, in the preceding article.
Hence the intellect which has more of the light of glory will see God the more perfectly; and he will have a fuller participation of the light of glory who has more charity; because where there is the greater charity, there is the more desire; and desire in a certain degree makes the one desiring apt and prepared to receive the object desired. Hence he who possesses the more charity, will see God the more perfectly, and will be the more beatified.
For Aquinas, this “given” faculty of divine intellect enables one to have a “fuller participation of the light of glory.” Newadvent.org defines charity as the following:
Its origin, by Divine infusion. “The charity of God is poured forth in our hearts, by the Holy Ghost” (Romans 5:5). It is, therefore, distinct from, and superior to, the inborn inclination or the acquired habit of loving God in the natural order.
The inequality of given divine charity is determined by God; it is a “Divine infusion….by the Holy Ghost.” We see in another passage that there is an order in charity. That is, there is an inequality of charity determined by God.
Aquinas asks, “Whether there is order in charity?” (II-II.26.1). He responds: “Consequently there must needs be some order in things loved out of charity, which order is in reference to the first principle of that love, which is God.”
He then asks, “Whether the order of charity endures in heaven?” (II-II.26.13) He responds:
Nature is not done away, but perfected, by glory. Now the order of charity given above (A2,3,4) is derived from nature: since all things naturally love themselves more than others. Therefore this order of charity will endure in heaven.
Notice that the perfection of each is limited by each person’s nature. This must mean that Aquinas holds to a form of natural inequality. He expands on this:
The order of charity must needs remain in heaven, as regards the love of God above all things. For this will be realized simply when man shall enjoy God perfectly. But, as regards the order between man himself and other men, a distinction would seem to be necessary, because, as we stated above (A7,9), the degrees of love may be distinguished either in respect of the good which a man desires for another, or according to the intensity of love itself. On the first way a man will love better men more than himself, and those who are less good, less than himself: because, by reason of the perfect conformity of the human to the Divine will, each of the blessed will desire everyone to have what is due to him according to Divine justice. Nor will that be a time for advancing by means of merit to a yet greater reward, as happens now while it is possible for a man to desire both the virtue and the reward of a better man, whereas then the will of each one will rest within the limits determined by God.
Putting this all together, what we see is that each person is perfected in heaven to the extent that his or her nature allows. Perfection, then, is perfection to the “limits determined by God.” In the next paragraph, he says that it is “according to his [or one’s] capacity.” For Aquinas, natural inequality endures into heaven. The “spiritual” kingdom is characterized by inequality determined by natural inequality. The external order endures and holds in the spiritual kingdom.
Calvin, however, holds that there is equality in the spiritual kingdom (from his commentary on 1Cor. 11):
Here the man is placed in an intermediate position between Christ and the woman, so that Christ is not the head of the woman. Yet the same Apostle teaches us elsewhere, (Galatians 3:28,) that in Christ there is neither male nor female. Why then does he make a distinction here, which in that passage he does away with? I answer, that the solution of this depends on the connection in which the passages occur. When he says that there is no difference between the man and the woman, he is treating of Christ’s spiritual kingdom, in which individual distinctions are not regarded, or made any account of; for it has nothing to do with the body, and has nothing to do with the outward relationships of mankind, but has to do solely with the mind — on which account he declares that there is no difference, even between bond and free. In the meantime, however, he does not disturb civil order or honorary distinctions, which cannot be dispensed with in ordinary life. Here, on the other hand, he reasons respecting outward propriety and decorum — which is a part of ecclesiastical polity. Hence, as regards spiritual connection in the sight of God, and inwardly in the conscience, Christ is the head of the man and of the woman without any distinction, because, as to that, there is no regard paid to male or female; but as regards external arrangement and political decorum, the man follows Christ and the woman the man, so that they are not upon the same footing, but, on the contrary, this inequality exists.
He also wrote (Commentary on Matt. 19:7): “Besides, political and outward order is widely different from spiritual government.”
Calvin’s doctrine of the two kingdoms allows for a legitimate hierarchical external order and fundamental spiritual/eschatological equality. The external order does not endure into heaven. Why? Because one is justified by faith alone. At the moment of faith, one is reconciled and has peace with God. He or she is equal (eschatologically speaking) with the oldest and wisest believer. There is an inequality of rewards, but not according to the extent that grace could perfect one’s nature.
The traditional Reformed view of the two kingdoms does full justice to the faith deposited in Scripture. There is outward and visible inequality (civil and ecclesiastical orders) and spiritual and invisible equality (eschatological kingdom). The former will pass away and the latter with be revealed.