Church of the Great God is "non-Trinitarian." Simply put, this means that we do not believe in the traditional, man-made hypothesis of a triune God (that is, "one God in three co-equal Persons"). The Trinity doctrine cannot be found in the Bible, as it was patched together by Catholic theologians hundreds of years after the deaths of the apostles and the completion of Scripture. Instead, Trinitarianism is a mixture of Jewish, Greek, and Roman philosophies, loosely based on a handful of Bible verses snatched out of context or interpolated into the text.
Scripture reveals God the Father to be the Supreme Deity, and the Son, Jesus Christ, while certainly a divine Being, is in all things submissive to the Father (see John 6:38; 14:28). The Holy Spirit is the presence and power of God, the essence of the divine mind that both Father and Son use to do Their work. It is not a separate being, anymore than the "spirit in man" (I Corinthians 2:11) is a separate being inside each human.
Scripture also reveals that, rather than being limited to two (or three) Beings, the God Family is in process of expanding through God's plan of salvation. Each true Christian is a son or daughter of God the Father and a brother or sister of Jesus Christ (Mark 3:35). As such, true Christians are members of the God Family, and will, if they remain faithful to the end, be changed into spirit members at the return of Jesus Christ to this earth.
Although this is astounding when one hears it for the first time, it is fully borne out in God's Word. Romans 8:29 tells us that the Father is conforming saints "to the image of His Son, that He [Jesus Christ] might be the firstborn among many brethren." Notice that He is the firstborn, indicating preeminence over others, not the "only-born." Likewise, Colossians 1:18 identifies Jesus Christ as "the firstborn from the dead," meaning that others will also be rise "from the dead" into the God Family when resurrected at Jesus Christ's return (see Revelation 1:5). Additionally, Ephesians 3:14-15 says that "the whole family in heaven and earth is named" after the Father. The saints have taken on the Family name, showing that they are already part of that Family Kingdom (Colossians 1:13), even though they will not be complete until they are transformed into spirit beings (compare John 3:3-8; I Corinthians 15:50).
By contrast, the Bible never mentions the Holy Spirit in the context of a family relationship, nor of being a member of the God Family. Scripture speaks of the Spirit as the power (Acts 1:8) or mind of God, the power of love and of a sound mind (II Timothy 1:7). Since it emanates from God, it can thus be said to be "poured out" (Titus 3:5-6), "breathed" (John 20:22), and used to "fill" (Acts 2:4) and "anoint" (Acts 10:38).
Finally, God's Word also reveals that the Father and the Son are not equal. In John 14:28, Jesus states unambiguously, "My Father is greater than I." Similarly, Paul tells the congregation in Corinth that "the head of Christ is God" (I Corinthians 11:3), clearly declaring that God and Christ are not equal. They are both divine—both God Beings—but fulfill very different roles.