In order to be a noble and honorable witness for the Christian message and for the Christian worldview, it is absolutely essential that you have a solid theological foundation under you. Without such a foundation, you run the risk of misrepresenting Christianity, of not being prepared to provide a reason for the hope that is in you, and of creating a lot of unnecessary frustration. In other words, you risk being less than honorable in your witness to God’s truth. You risk not only your credibility, but the credibility and perceived integrity of God’s word. It is the truth of God’s word that the Holy Spirit applies to the human heart and thus, frees the sinner from his or her sin. Additionally, unleashing divine truth is the very best defense you could give of the Christian worldview. In order to do this, a basic understanding of the core components of Christian doctrine is necessary. And there is no better place to begin your journey toward such an understanding, than with a basic, but serious study of the nature of the Christian God who reveals Himself in the Christian Scriptures.
Naturally in the system of theology and in apologetics the doctrine of God is of fundamental importance. We must first ask what kind of God Christianity believes in before we can really ask with intelligence whether such a God exists.
-Cornelius Van Til
The atheist claims that God does not exist. The agnostic claims that humanity cannot know whether or not God exists. Judaism claims that God is not Triune. Islam claims that Allah alone is God. Hinduism has within it strains of theistic belief that range from polytheism, monotheism, and even monism. Buddhism is monistic. It denies the existence of a personal God. To add to the false religions of the world, there are those who claim Christianity as their system of truth but who deny the historic Christian view concerning the nature of God. In short, they deny the Trinitarian nature of God. Among these groups is one prominent name: T.D. Jakes. Christian apologetics must not only deal with the atheist, the agnostic, and competing false religions, but it must also deal with false these false teachers who claim to know God, but in reality, do not.
Christian apologetics is set to defend, not the existence of some god in general. Christian apologetics is not set to defend the idea that some god in general probably exists. Christian apologetics is not charged with the mission of defending the view that Christianity is more probably true than competing philosophies and religions, whatever they might be. Christian charged with the task of giving a reason for the hope that is in us and that hope is indelibly tied to the self-contained ontological Triune God revealed in Scripture.
The Christian Doctrine of the Trinity
The Christian belief and confession that God is one being eternally existing in three persons is a non-negotiable of Christian faith. In other words, it separates true believers from false ones.
A certain preacher once said about the doctrine of the Trinity: “as he that denies this fundamental article of the Christian religion may lose his soul, so he that much strives to understand it may lose his wits.” [W.G.T. Shedd, Reformed Dogmatics, v. I, pg. 250]