4. Doctrine of the Trinity

Important Passages

James 2:19: “You believe that there is one God. Good! Even the demons believe that – and shudder.”

Matthew 28:19: “Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit”

Matthew 3:16-17: “And when Jesus was baptized, immediately he went up from the water, and behold, the heavens were opened to him, and he saw the Spirit of God descending like a dove and coming to rest on him; and behold, a voice from heaven said, “This is my beloved Son, with whom I am well pleased.”

John 1:1: “In the beginning was the Word, and the Word was with God, and the Word was God.”
Acts 5:3-4: “Then Peter said, ‘Ananias, how is it that Satan has so filled your heart that you have lied to the Holy Spirit and have kept for yourself some of the money you received for the land? Didn’t it belong to you before it was sold? And after it was sold, wasn’t the money at your disposal? What made you think of doing such a thing? You have not lied just to human beings but to God.”

We cannot fully understand everything about the nature of God (of course) but we can know truths about God because of what he has revealed in Scripture.

The Doctrine of the Trinity means that there is one God who eternally exists as three distinct Persons — the Father, Son, and Holy Spirit. Stated differently, God is one in essence and three in person. These definitions express three crucial truths: 

  1. The Father, Son, and Holy Spirit are distinct Persons
  2. Each Person is fully God, 
  3. There is only one God.

Note that this is not an explanation how God is one in being and three in person, but a description that God is one in being and three in person. We accept this truth because Scripture bears witness to it, even though we may not understand this mystery fully. 

Many of today’s cults and heresies deny one or more of these three truths. 

Source:
1. http://www.desiringgod.org/articles/what-is-the-doctrine-of-the-trinity