Our belief in the triune nature of God is fundamental in defending the truth of the Christian faith. It is this belief that separates us from every other religion.
The doctrine of the Trinity states that in the unity of the Godhead there are three eternal and coequal persons: Father, Son and Holy Spirit. These three are the same in essence but distinct in role. Each is a separate person, yet each is identified as God: Father (1 Corinthians 8:6), Son (John 20:28; Titus 2:13), and Spirit (Acts 5:3–4). For example, with regards to the doctrine of creation, the Bible clearly teaches that the creation of the world was brought about by the triune God. While the Father is at the forefront in the work of creation (1 Corinthians 8:6), the work of the Son is recognized (John 1:1–3; Colossians 1:16; Hebrews 1:2), as is the work of the Holy Spirit (Genesis 1:2; Job 26:13, 33:4; Psalm 104:30).
Today, however, one of the primary problems in Christian apologetics is that when many Christians defend the faith they end up defending a generic theism. We must realize that theism does not equal Christianity. If all we do is prove that there is something out there that is bigger and better than us, then we have not defended the Christian faith.
We need to realize the theological reality that God is our Creator and man is in rebellion against Him.
Many Christians tend to defend a generic theism because of an assumed neutrality between Christians and non-Christians in their apologetic methodology. The problem with this is that the unbeliever, by virtue of his unbelief, will take any given evidence and interpret it according to his unbelief (Acts 17:23; cf. Romans 1:18). By thinking there is neutrality when it comes to interpreting God’s world, we often give up the very authority that we are called to stand on: Scripture (Titus 1:9). We need to realize the theological reality that God is our Creator and man is in rebellion against Him (Romans 1:18–32). Therefore, you cannot base your apologetic methodology on the unbiased decisions of fallen man, because he will not make unbiased decisions (Romans 8:6–8; 1 Corinthians 2:14). God’s creatures have no right to judge the existence of their Creator.
The main problem with trying to defend a generic theism is that theists will face the same judgment as nontheists (John 5:25–29). We are saved from the wrath of God by the grace of God, which comes through the gospel of Jesus Christ, not by believing in a generic theism (see Acts 17:30–31; Romans 10:9, 17). Salvation is an action on the part of the triune God because all three members of the Trinity were involved in redeeming humanity. We were chosen by the Father (Ephesian 1:4), redeemed by Jesus (Ephesians 1:7), and sealed by the Holy Spirit (Ephesians 1:13).
As Christians we are not supposed to make theists out of people; we are called to defend the Christian faith (1 Peter 3:15). This means sharing what the triune God of creation has done for us in the gospel (1 Corinthians 6:11).