“usus rationis: the use of reason;
specifically, the use of reason in theology.”Richard Muller, Dictionary of Latin and Greek Theological Terms: Drawn Principally from Protestant Scholastic Theology, Term: usus rationis.
Can the use of reason be abused in the work of theology? We know that human reason enables the Christian to come to many truths, but can it also get in the way of the truth? How about the methods used which are considered rational or fair uses of human reason? Indeed, both human reason itself and the methods constructed by reason can serve as impediments to the truth. The Reformers recognized this double-edged sword called human reason and accounted for it in their work. Muller observes,
“In order to avoid what they [the Protestant Orthodox] saw as the abuse of reason in medieval scholasticism, early modern Socinianism, and the new rationalist philosophies of the seventeenth century, the Protestant orthodox distinguished between legitimate use of reason in theology.”Muller, Dictionary, Term: usus rationis.
The Protestant Orthodox understood the proper use of reason as divided into three uses – the organic, instrumental, or ministerial uses of reason. Additionally, there was one improper use – the magisterial use. Of the three proper uses Muller observes,
“The ordinary, instrumental, or ministerial use of reason recognizes the inherent rationality of human beings and of human discourse, including theology. Reason thus is used organically, according to its place among the natural faculties of soul, and instrumentally or ministerially, as a tool to aid to logical or rational discourse.”Muller, Dictionary, Term: usus rationis.
In a similar vein the Reformed Orthodox also differentiated between different uses of philosophy. Again, the different uses are divided into three:
“(1) the organic use, i.e., the use of philosophy to train the reason, analyze arguments, and serve theology in a purely instrumental manner.”Muller, Dictionary, Term: usus philosophiae.
“(2) the use for argument or for proof, the use of philosophy to adduce ancillary arguments to support theological proof; this use is possible only in the articuli mixti…in which both theology and philosophy have a role, e.g., the existence of God.”Muller, Dictionary, Term: usus philosophiae.
“(3) the use for demolition (of an argument), the use of philosophy to refute error and find logical gaps in argumentation.”Muller, Dictionary, Term: usus philosophiae.
In sum, philosophy can be used to train thinkers how to think, offer support to theological arguments where relevant, and serve as a secondary form of argumentation in the work of defeating other arguments.
As for the magisterial use of reason, a faulty use of reason, the issue lies in asking, “What serves as the source of theological content?”
“When, however, reason assumes a magisterial function and presumes to teach theology its contents, it oversteps its limits; the content of theology must rest solely on revelation.”Muller, Dictionary, Term: usus rationis.
An example of the magisterial use of reason may be when scholars conclude that the Bible must have errors in the text and/or in historical reliability and/or in scientific reliability because the manuscript evidence says so and/or current archeological stances say so and/or “Look over there, ancient cosmologies!” = scientifically wrong. In these cases, man’s reason is dictating the content of theology rather than revelation.
Certainly, reason is a fundamental part of the human experience and the formulation of theological thought. Our use of reason is of course human and should be logical but all under the lordship of Christ and His revelation. For example:
1.) It is reasonable and logical to believe that Jesus raised Lazarus from the dead.
2.) Furthermore, it is reasonable and logical to employ historical, archeological, philosophical etc data and arguments to support (1).
3.) For the Christian, it is neither reasonable nor logical to conclude that Lazarus did not rise from the dead nor was Christ able to raise Lazarus even after we look all those who remain in their graves and interview millions of people incapable of raising the dead.
In like manner,
1′.) It is reasonable and logical to believe that every jot and tittle of the Greek and Hebrew is kept pure in all ages, never to pass away.
2′.) Furthermore, it is reasonable and logical to employ historical, archeological, philosophical etc. data and arguments to support (1′).
3′.) For the Christian, it is neither reasonable nor logical to conclude that some or much of the Bible has passed away given the manuscript evidence and some’s current inability to reconcile this or that reading.
Human reason has its place, and that place is in submission to Christ and His revelation.