Trinitarianism is the belief in one God who exists in three persons—God the Father, God the Son, and God the Holy Spirit. This belief is built on two clear biblical teachings. First, the Bible teaches there is only one God (Deuteronomy 6:5, among others). Second, there are three unique persons referred to as God in Scripture—Father, Son, and Spirit.
Is Trinitarianism biblical? What exactly is Trinitarianism?
The Old Testament begins with the assumption of one God who created the heavens and the earth: "In the beginning, God created the heavens and the earth" (Genesis 1:1). This was later affirmed in the Mosaic Law (Deuteronomy 6:5) and taught throughout the remaining history of the Old Testament.
In the New Testament, Jewish leaders continued in their belief that God is one, yet Jesus claimed to be one with the Father (John 10:30) and called himself the "I AM," a term asserting His equality with God (compare Exodus 3:14 with John 8:57-59). This led His opponents to pursue Christ's death, since this was considered blasphemy to the Jews. Yet Jesus proved this truth through His own resurrection, with His followers claiming Jesus as Lord and God (John 20:28), something that would be repeated throughout other New Testament writings.
Later, in Colossians 1:16-17, Paul makes it clear that Jesus is eternal, as part of the Godhead, and that He was involved in the creation of all things: "For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him. And he is before all things, and in him all things hold together." His intent was to provide clarity to the teaching that Jesus is eternal, is Creator, and is God, one with the Father and the Spirit (Genesis 1:1-2).
The Holy Spirit, like the Father and the Son, is also referred to as God. As the third person of the one Triune God, He is given the names of deity. In Acts 5:3-4, the apostle Peter stated, "Ananias, why has Satan filled your heart to lie to the Holy Spirit and to keep back for yourself part of the proceeds of the land? While it remained unsold, did it not remain your own? And after it was sold, was it not at your disposal? Why is it that you have contrived this deed in your heart? You have not lied to man but to God." Other verses make similar reference:
1 Corinthians 3:16: "Do you not know that you are God's temple and that God's Spirit dwells in you?"
2 Corinthians 3:17: "Now the Lord is the Spirit, and where the Spirit of the Lord is, there is freedom."
Hebrews 9:14: "how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God." (Here we see all three persons of the Triune God mentioned by name, including the Spirit referred to as "eternal," something only possible of God.)
In addition to being called by the names of deity in Scripture, the Holy Spirit performed acts only God could perform. Some of these include creation (Genesis 1:2), miracles (Galatians 3:2-5), redemption (Ephesians 4:30), and giving supernatural gifts (Acts 2:4; 1 Corinthians 12:4-11).
Many illustrations have been offered to help explain the concept of the Trinity. Though none is perfect, many have found the following helpful. Rather than 1+1+1=3 as is often thought, the Trinity is 1x1x1=1, revealing three distinct units yet one unified being.
Another illustration is found using the three states of water. Water can exist as a liquid, solid, or gas, yet remains the same. In all three states, it is still H20.
A third illustration often used is a triangle. This shape consists of three angles, yet remains one shape. In all three illustrations, we find the concept of "three in one" in operation, similar to the Bible's presentation of the Triune God.
Throughout the history of the church and yet today, many alternative views have been proposed to explain the relationship of Father, Son, and Spirit presented in the Bible. The most common have been Tritheism (the common accusation of Muslims regarding the Christian view of God), Modalism, and Arianism.
Tritheism teaches that the Father, Son, and Holy Spirit represent three different gods. This is a common misunderstanding or accusation made by non-Christian religions regarding the concept of the Trinity. However, this belief is distinctly different since Trinitarianism acknowledges one God who consists in three persons, not three distinct gods.
Modalism (also sometimes referred to as Sabellianism after its founder Sabellius in the third century) is the belief that God is only one Person who appears in different roles at different times. The primary problems with this view are that all three persons of the Trinity are referred to in Scripture as eternal, that the Father and the Son speak to one another in Scripture (Matthew 3:17, 17:5; John 12:28), as well as the fact that there are passages that mention Father, Son, and Holy Spirit together in the same context (Matthew 3:16-17, 28:19; 2 Corinthians 13:14). This teaching is found today in the Oneness Pentecostal movement and United Apostolic Churches.
Arianism, named after its founder Arius, is a third century teaching that denies the full deity of Jesus and claims He was a created being. This teaching of Jesus as God's first creation is found today in religious groups such as the Jehovah's Witnesses and Mormon Church. Within historic Christianity, however, this view was condemned as heretical at the Council of Nicea in 325, since Jesus is eternal according to Scripture (John 1:2; Colossians 1:16-17).
In summary, Trinitarianism is the belief in one God who exists in the three Persons of Father, Son, and Holy Spirit. It is a biblically-based understanding of the three Persons referred to as God in Scripture, regarding their eternality, involvement in the creation of all things, their supernatural power, their names, their acceptance of worship as God, and other attributes that could only refer to deity.
While no perfect illustration exists, we see other examples of "three in one" in nature. Further, no competing theological belief, such as Tritheism, Modalism, or Arianism, can provide an alternative that accurately handles the many Scriptures referring to each person of the Trinity as deity. Therefore, Trinitarianism is a biblical belief and one essential to our understanding of who God is and how He operates in our world.
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Is there proof for monotheism?
The attributes of God, what are they?
Is belief in the pre-existence of Jesus biblical?
Who is the Holy Spirit?
Truth about Theology