One huge area of interest for the Christian philosopher is that of the relationship between man’s natural practical reason and the virtues that he may acquire through his faculties and the supernatural virtues that no natural faculty can help to achieve but are, nonetheless, requirements for entry into the City of God. Peter Martyr said that the mean between vices (which is the essence of virtue) may only be found by looking to the scriptures. At first this idea seems like that of a biblicist who seeks to do violence to nature in order to prove man’s need of the supernatural. However, Martyr is a big fan of natural law (he calls it prolepseis) even saying, “we must always accept the view that ‘Reason always encourages one to better things.'” (Commentary on Aristotle’s Nicomachean Ethics, p. 286).
How do we solve this dilemma? Does Martyr contradict himself? Can men find the mean by use of reason? I think if we assume (a) that Christianity and pagan philosophy are incompatible or (b) that there is a dichotomy between reason and faith so that we must always make a choice between one or the other then we must conclude that he does contradict himself. The person who holds to (a) would consider this good while the person holding to (b) would consider Martyr irrational.
In order to answer these questions we must distinguish between (1) acquired and (2) inspired (or infused) virtues. The acquired virtues are worthless coram Deo while the inspired ones are made perfect by Christ’s righteousness. No. (2) does not only consist of the theological virtues of faith, hope, and charity but also those that man can naturally acquire (but does not in this case) such as prudence, fortitude, and temperance. The difference between the believer’s moral virtues and those of the unbeliever is that the former are directed to God while the others are directed at an infinite variety of earthly ends.
Therefore, Martyr says that Christian right reason seeks after the mean of (2) in the scriptures because they surpass natural reason and because the effects of sin have deemed man’s rational faculty unreliable. I believe Martyr follows the basic structure that Martin Luther presents in his Lectures on Galatians to perfect Aristotle’s virtue theory with the more certain truth of the Christian faith. Luther says that in theology “doing” has a different meaning than in morals:
Thus it has a completely new meaning; it does indeed require right reason and a good will, but in a theological sense, not in a moral sense, which means that through the Word of the Gospel I know and believe that God sent His Son into the world to redeem us from sin and death. Here ‘doing’ is a new thing, unknown to reason, to the philosophers, to the legalists, and to all men; for it is a ‘wisdom hidden in a mystery’ (1 Cor. 2:7). In theology, therefore, ‘doing’ necessarily requires faith itself as a precondition […] a new reason must come into being, which is the reason of faith. Therefore ‘doing’ is always understood in theology as doing with faith, so that doing with faith is another sphere and a new realm, so to speak, one that is different from moral doing. (Lectures on Galatians, pp. 262, 263)
Thus in order to find the mean that counts as virtue coram Deo natural reason is not enough. One must look to the supernatural wisdom, a reason of faith, found in the Holy Scriptures. This is not the case of faith doing violence to natural reason, rather it is the case of faith perfecting natural reason by directing it toward its supernatural end in the vision of God. Once faith has been found through the hearing of the word and the inspiration of the Spirit men can acquire virtues that apply both to the civil and spiritual realms through the use of right reason.