Some of my previous posts at TCI have contended that there is a rational method for verifying religious claims, and have outlined in more detail how this method works for Protestants. I want to build slightly upon these arguments to make another clarification about method. In my post about religious studies in general, I noted that “[i]nsofar as we can discover the essences of things by means of observing their properties and behaviours, we can come to know what kind of effects certain objects naturally produce. This in turn allows us to form historical inferences about what types of causes certain effects require as their most probable explanation.”
In one of my replies to Dr. Feser, I noted how this provides a rational basis for belief in the inspiration of scripture, by means of Francis Turretin’s writings, which give “extensive arguments from historical evidence for the reliability of the apostles and Moses as historical witnesses; this established, when they testify to miraculous confirmation of their message, and then claim to be divinely inspired, they are credible witnesses to this divine confirmation of their claim to inspiration.” In a further reply, I sketched this rational basis in more detail. In my final instalment to that interlocution, I summarized how this method could exclude putative claims to revelation: “Moses’ tests for false prophets were two: lack of miracles, and contradiction with previous revelation. Insofar as scripture is simply prophetic written texts, if our question is how to exclude books from scripture, these tests provide two ways. That is, if the proposed additional writing contradicts the Bible, or provides no miraculous attestation to its message, we can safely dismiss it.”
I also defined the historic Protestant claim of sola scriptura more precisely than is sometimes done. That is, I noted that for scholastic Protestants, sola scriptura was not meant to deny the existence and full authority of natural revelation, but rather only the infallibility of Popes, councils, and tradition. Sola scriptura was a claim made in a particular historical context, and the sola was aimed at particular challengers, not every conceivable source of knowledge. Of course, some Protestants did broaden that claim to attack natural theology, but that was only one version of Protestantism, not the whole.
The bigger question, though, is whether this broader kind of sola scriptura is rational and biblical, that is, whether it is true. In fact it is none of these things. Rational reflection upon reality still leads to a traditional metaphysics and theology, and scripture supports the same. The biblical texts that support sola scriptura do not view God’s natural revelation as a rival to his written revelation. While it is true that scripture is more authoritative than human wisdom, it is not more authoritative than divine revelation; and while human reasoning from what has been created can go awry, so can reasoning from the biblical text.
The scriptures recognize the existence and authority of natural revelation. And insofar as they describe natural revelation as existing in nature itself, they imply that it was the very first revelation humanity ever received. When they further add that God does not lie or contradict himself, they require readers of the Bible to seek harmony between the text and the created order. Obeying this call was the theological method of the scholastic Protestants, and if we seek to be both rational and biblical, it should be ours today.