Natural Theology & Christian Apologetics: A Brief Primer

The topics of apologetics and natural theology are, to say the least, complex and controversial. Yet as Christians we have to deal with them. So let us try informed by God’s word and the history of the Church.

We must define our terms, and while broad summary definitions can generally be agreed upon by those conversant with these topics, broad summary definitions are often of limited help. Still, we must start broadly while seeking specificity. The term theology comes from two Greek terms theos or God and logos or word, deed or word about, and so the term is broadly defined as the study of God or word about God. Some have argued that since the term itself is of Greek derivation the enterprise based upon it is corrupted at the outset with a non-Christian character. This argument commits what is called the genetic fallacy—thinking that the origin of a term or concept automatically discredits its use or eternally establishes its meaning. But words do not define themselves and previous definitions used by others do not bind us to define terms only in the previous ways they have been defined and used.

Christian apologetics is generally agreed to be the defense of the Christian faith and life. Our term “apologetics” is derived from the Greek term apologia, which can be defined as defense, reason or explanation. So, in this instance “defense” means a rationally coherent explanation that accurately expresses the truth of God’s written word. Thus, the standard for rationality is God as he has communicated himself through his word written. A number of truths are implied, rooted, or presupposed within the ability to give a rationally coherent explanation that accurately expresses God’s word.

This definition of apologetics implies that God effectively communicates some truth to all humans, that all humans have some capacity to understand and reason in accord with God’s truth or revelation, and that there is an unavoidable objectivity and subjectivity to reality and human reception and understanding of truth. By “objectivity” I mean that there is an aspect to reality that is what it is regardless of what anyone thinks or feels about it; it is the same for all people for all times and all places. By “subjectivity” I mean that there is an aspect to reality that is personal, and with respects to human knowledge it emphasizes the individual person’s experience with and perception of reality.

Psalm 19 and Romans 1:16-32 in particular tell us that in and through creation God reveals himself. In particular, Romans 1:20 tells us that God’s invisible attributes, his eternal power and divine nature are clearly seen through what has been made (by him) so that all people are without excuse (for their sin). Because some in the history of Christian theology have used the term natural as a synonym for the physical creation, some have spoken of a natural theology—what people either can or do know about God through the physical creation. In the history of Christian theology there are fundamentally two ways in which this natural theology has been conceived.  

One way is to use the term natural theology to refer to what people (despite sin) can and do know regarding God by virtue of the fact that they are created in God’s image and, as Psalm 19 and Romans 1 affirm, have God’s revelation made known to them by God. They have true, genuine knowledge of God because God has caused them to have it. They can deny they have it, but they still have it. When natural theology is used in this sense it is being used as a distinct category, although not necessarily disconnected one from what can be rightly called supernatural theology. The latter is what is given to the sinner saved from his or her sin by what Jesus accomplishes and the Holy Spirit applies to him or her in their salvation. This salvation is eternal life and described by Jesus as knowledge of God (John 17:3). Thus, the sinner’s salvation is rightly regarded as a supernatural knowledge of God, or we could say supernatural theology that is not available merely through the physical creation. Thus, if one maintains the use of natural theology as defined above one must distinguish that kind of natural theology from the supernatural theology that is a synonym for salvation or the eternal life God gives when he reveals the truth regarding Jesus as Lord and Savior (Matt. 11:28-30; John 8:31-34).

Yet, there are some difficulties in understanding the relationship between this natural theology as described above to the supernatural theology that is equated with salvation or eternal life.

One of these difficulties is that in the history of Christian theology this term natural theology has been used not merely for what the non-Christian can and does know regarding God through the physical creation, but also what the Christian is able to learn about, reason according to and know of God through the physical creation as he or she is supernaturally illumined by the Holy Spirit in harmony with God’s written word. The Old Princeton theologians (1812-1921) used the term “right reason” to refer to this supernaturally illumined reasoning that the Christian possesses through the Holy Spirit and God’s written word.

Here we have the blurring of lines between the two categories of natural and supernatural theology. Is there any legitimacy to this? Absolutely there is. After all, did not the same Triune God that created the physical universe do this by his power and for his glory both of which can be rightly deemed supernatural? So, in what sense should the terms natural and supernatural, and the realities to which the terms refer be distinguished or not distinguished?

B. B. Warfield (1851-1921) in his treatment of the biblical doctrine of revelation affirmed that the categories by which we can rightly identify revelation or knowledge of God can be classified according to three couplets, which he called species of revelation: 1) general and special; 2) natural and supernatural, or 3) creational and soteriological. In his essay on the topic Warfield went on to explain in what ways these species of God’s revelation could be described and distinguished according to these terms.[1]

When giving a reason for the hope that is within us as Christians we cannot help but address matters that are in God’s creation or nature, and are expressing a particular interpretation of those matters required by and revealed in God’s written word through the Holy Spirit’s illumination to us. This defense or explanation must be in some sense understandable to the non-Christian. If not, then what would be the point of talking to them? The non-Christian does have in some sense what can be rightly called a natural theology, but it needs to be replaced by a saving supernatural theology, only then can a sinner begin to have a God-glorifying natural theology. It is the Christian’s duty and privilege to participate with the Holy Spirit in bringing “right reason” to the non-Christian. In this we see one of the ways that Christian apologetics and natural theology are related.