We believe there is one God, eternally existent in three Persons: Father: Son and Holy Spirit.
The Bible speaks of one God but attributes the characteristics of God to three Persons: Father, Son and the Holy Spirit. God the Father created all things and planned the redemption of His people from all eternity (Genesis 3:14-15, Ephesians 1:3-12). God the Son (Jesus) accomplished that redemption on the cross (Romans 3 21-24), Galatians 3:13-14). God the Spirit (The Holy Spirit) applies the benefits of that eternal redemption to all believers (John 3:5-8, Titus 3:4-7). The doctrine of the Trinity is a way of describing this biblical revelation of the nature of God. It states that God is one in essence, but that He exists in three Persons who are equal, eternal, inseparable, and interdependent. Persons actually fails to accurately describe God because it can give the impression of three separate individuals. A more precise view is that God is one being with three personal self - distinctions.
Why should we accept the word Trinity as a way to describe God when it isn’t in the Bible? Heretical groups came on the early Church scene and denied either the deity of Christ or that of the Holy Spirit. This drove Christians to search the Scriptures to come up with a formal way to describe the Bible’s teaching on the nature of God. The doctrine of the Tri-unity was the result. Tertullian, an Early Church father, was the first to use the term Trinity in 215 AD.
The Bible teaches that we have one God (Deuteronomy 6:4, Isaiah 43:10, I Corinthians 8:4-6, Ephesians 4:4-6). At the same time, that one God is revealed progressively throughout Scripture as three Persons:
• God the Father, God the Son, and God the Holy Spirit are active in Creation (Genesis 1:1-2, Colossians 1:16-17)
• Isaiah prophesies that the one born of the virgin would also be Immanuel, God with us (Isaiah 7:14) and later calls the Messiah Mighty God and Eternal Father (Isaiah 9:6).
• The New Testament calls the Father God (John 6:27, John 20:17, I Corinthians 8:6, Galatians 1:1 Ephesians 4:6, Philippians 2:11 Peter 1:2).
• The New Testament explicitly declares Jesus Christ to be God (John 1:1, John 20:28, Titus 2:13, Hebrews 1:8).
• The New Testament writers recognize the Holy Spirit as God (Acts 5:3-4, I Corinthians 2:10-11, I Corinthians 6:19, John 3:5-6, Titus 3:5).
• The New Testament writers speak of the presence and work of the Father, Son, and Spirit in one breath (Matthew 28:19, Mark 1:10-11, Luke 10:32, 2 Corinthians, 1Peter 1:2).