The doctrine of the trinity is vitally related to truth. Although the word, “trinity” never appears in Scripture the doctrine of the triune God does. The Godhead is such a doctrine that cannot be fully understood as this is beyond our limited knowledge and understanding as mankind. Our mind cannot comprehend such a mystery of the divine triune Godhead. How can man understand that three persons of the Godhead are distinct, but not separate and all divine in nature.

Here are some examples found in Scripture of the divine nature of the Father, Son and Holy Spirit.

God, the Father – “For what if some did not believe? shall their unbelief make the faith of God without effect? God forbid: yea, let God be true, but every man a liar; as it is written, That thou mightest be justified in thy sayings, and mightest overcome when thou art judged.”  (Rom 3:3-4). “Now I say that Jesus Christ was a minister of the circumcision for the truth of God, to confirm the promises made unto the fathers:”  (Rom 15:8).

God, the Son – “Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.”  (Joh 14:6) “But ye have not so learned Christ; If so be that ye have heard him, and have been taught by him, as the truth is in Jesus:”  (Eph 4:20-21).

God, the Holy Spirit – “But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which proceedeth from the Father, he shall testify of me:”  (Joh 15:26) “Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come.”  (Joh 16:13).

The Four Essentials of the Trinity

1. There is only one true God.
2. One God who eternally exists in three persons.
3. The three are equal and attribute the same divine nature.
4. While the three are fully and completely divine, the persons are not identical.

Monotheism
There is no other doctrine that is more important than this. The doctrine that there is One God is the fundamental truth that holds all other doctrines together (Deut. 6.4) Both the Old and New Testaments affirm this truth. See John 17.3, I Tim. 2.5, and Jam. 2.19. As there is only One God the worship of another god is idolatry. All idolatry is evil, foolish, harmful and wrong. Those who worship another without repentance before the final judgment will be punished in hell forever. Idolatry is not always the worship or following of another world religion it can be anything you put before the One true God of Holy Scripture. God deserves full and complete worship.

Practical Implications
There are two clear practical implications of the divine Godhead. Firstly, the revelation of God in Christ. God, the Father is revealed in his Son, Jesus Christ. We can know the Father through the Son. Secondly, the Godhead made salvation possible. The Spirit kept Christ pure from sin and preserved him. The Son, Jesus Christ shed his blood for the forgiveness of sin and God, the Father raised Christ from the dead. Salvation truly was a work of the Trinity.

How can three be one?
The word “trinity” was coined by the early Church writer Tertullian. He was born in 160 A.D. in Carthage, Tunisia. He coined the term in about 200 A.D. He used the words “substance” and “essence” to speak of God’s oneness. God is one substance in three persons. This oneness of God is seen in many Scriptures one of which is Deut 6.4, “Hear, O Israel: The LORD our God is one LORD.” Also, see Joh 2.19 and I Cor. 8.4. The doctrine of the Trinity is a mystery and belongs to God. “The secret things belong unto the LORD our God: but those things which are revealed belong unto us and to our children for ever, that we may do all the words of this law.”  (Deu 29:29)