The document discusses why Christians believe in the Trinity despite the term not being found in the Bible. It summarizes that the Trinity is inherently biblical as the triune nature of God was revealed implicitly in the Old Testament and explicitly in the New Testament. The doctrine of the Trinity is based on two realities: there is one God, and the one God has eternally existed as three distinct persons - the Father, Son, and Holy Spirit - who are each fully God. The document provides scriptural support for these realities and concludes that we embrace the Trinity because God has revealed himself as triune in his word.