THE ONE WHO IS: the doctrine and existence of God
A Theological and Apologetics Handbook
by Dr. Kenny Rhodes
Self-knowledge and the knowledge of God “Our Wisdom, in so far as it ought to be deemed true and solid Wisdom,” John Calvin writes, “consists almost entirely of two parts: the knowledge of God and of ourselves. But as these are connected together by many ties, it is not easy to determine which of the two precedes and gives birth to the other.” Calvin concludes, “the knowledge of God and the knowledge of ourselves are bound together by a mutual tie.” Calvin understood the connection between our being and God’s being, self-knowledge and the knowledge of God. This connection exists because God is the source and ground of man’s being, for “in Him … we have our being” (Acts 17:28). Man has been created with an innate sense of God, an inward witness of the Divine— the sensus divinitatis. This “mutual tie” is our epistemological ground, that is, our being within God’s being grounds our knowledge of reality. Self-knowledge inextricably leads to the knowledge of God. This is the common ground upon which all mankind stands.
The Christian apologist can use this common ground to communicate the existence of God and the Gospel. This mutual foundation is being itself, along with the principles of logic, as demonstrated above. The laws of logic are innate to us, a priori, and confirmed to us, a posteriori, they are a part of the intellect’s operating system, which comes preinstalled from the Creator. Peter Kreeft writes, “Now the knowledge of the principles that are known to us naturally has been implanted in us by God; for God is the Author of our nature.” In utilizing these principles, we are participating in the Divine mind. We can use the light of the Divine Mind to demonstrate the existence of the Divine Mind. In a way, this exhibits the irrationality of the mind in sin. It is like using the light of the sun to prove that the sun exists or, conversely as atheists attempt to do; to use the light of the Son to prove that the Son does not exist. It is because of this noetic (intellectual) confusion that the necessity of demonstrating God’s existence becomes apparent.
The “sensus divinitatis” is so distorted and confused in mankind that a demonstration is needed to introduce sinful man to his Creator. A valuable illustration is seen in the case of Helen Keller. She was blind, deaf, and mute. Since all people are spiritually blind, deaf, and mute, this illustration is very fitting. Due to a childhood illness, Helen Keller became deaf, blind, and mute at a very young age. She was later taught to communicate with hand signals conveyed by touch on the palms of her hands. When she was told about God her answer was very enlightening. She said that she knew God was there but that she did not know His name. Thomas Aquinas expounds the related point, saying, “To know that God exists in a general and confused way is implanted in us by nature…. This, however, is not to know absolutely that God exists; just as to know that someone is approaching is not the same as to know that Peter is approaching, even though it is Peter who is approaching.” Helen Keller knew “someone was approaching;” she just did not know that it was Jesus approaching. Demonstrating God’s existence is really just reinstating the inner knowledge of God while removing all real and imagined obstacles to belief. Apologetics is simply just pre-evangelism. A demonstration of God’s existence as part of sharing the Gospel can be used by the Holy Spirit to infuse spiritual life. Therefore, we must be engaged in arguing for the existence of God. The restoration of belief in the existence of God alone only brings doxa knowledge. The Gospel still must be preached in order for the Spirit of God to regenerate and establish the soteric knowledge of God to the individual, thus bringing spiritual life.
Arguments for the existence of God only inform us “that God is” and not “who God is.” Aquinas writes, “For just as it is self-evident to us that a whole is greater than its part, so is it most evident to those who see the very essence of God that God exists, since His essence is His existence. But because we are unable to see His essence, we come to know His existence not in Himself but in His effects.” God’s existence, as stated earlier, would have been self-evident if man had not fallen into sin. But because of sin, the knowledge of God’s existence is confused and darkened. Now, man stands in need of a demonstration. The light of reason can never uncover the essence of God; it can only declare His existence, which is the doxa knowledge of God. So, it is through God’s effects that we can know “that He is.” People are God’s effects, and so God can be demonstrated to exist through our being and our self-knowledge. This is the existence of God demonstrated through the light of natural reason, which is available to all people. Our existence and self-knowledge flows to the knowledge of God’s existence. Any knowledge of God’s essence, “who God is,” must come to us by way of revelation, through God’s Word and God’s Spirit. This knowledge is still incomplete, for it is not the beatific knowledge awaiting all believers upon glorification in the presence of God. Now that God’s existence, “that God is,” has been demonstrated, we will turn our attention to “who God is.” The answer to the question, “what is God like,” comes to us by way of Scripture.
FOOTNOTES/ ENDNOTES  John Calvin, Institutes of the Christian Religion (Bellingham, WA: Logos Research Systems, Inc., 1997), I, i, 3.  Aristotle said, “that the first principles are known by immediate experience.” The mind has the capacity to have knowledge “installed” on it through the input of sense experience (a posteriori). The mind was designed by God to operate like a computer. Humans are born with a formatted hard drive with operating system (a priori the agens intellectus), with the capable of having knowledge written on it— the ability to know and understand. For a thorough discussion of knowledge, see Etienne Gilson, Thomistic Realism and the Critique of Knowledge (San Francisco: Ignatius Press, 1986), and Summa Theologiæ I. 79 “Of Intellectual Powers,” and Norman Geisler, Should Old Aquinas Be Forgotten (Bastion Books, Kindle Edition) chapter six “The First Principles of Knowledge.”  Peter Kreeft and Ronald K. Tacelli, Handbook of Christian Apologetics : Hundreds of Answers to Crucial Questions (Downers Grove, IL: InterVarsity Press,1994), 39.  Sin is so nefarious that atheists actually try to use the gifts that God has given them to disprove His existence. This seems to be the very definition of madness.  Helen Keller writes, “Mr. Brooks, I have always known about God, but until now I didn’t know His name.” cited by Harold E. Helms. God’s Final Answer (Maitland, FL: Xulon Press, 2004), 78.  Aquinas, Summa Theologica, I q.2 a.1 ad.1.  Aquinas, Summa Contra Gentiles, I. 21.  The three stages of the knowledge of God: doxa knowledge (all men), soteric knowledge (all believers), and beatific knowledge (glorified saints).