Perhaps someone has challenged you with, "The word ‘triune' is not in the Bible. So it isn't true!" You will not find "triune" in the Bible, but you will find that truth taught there. The Christians invented the word "triune" to confess a clear teaching of holy Scripture that God is "three in one."

We should rejoice that the true God is not like us, but that He is incomprehensible. "My thoughts are not your thoughts, and My ways not your ways." Because God is holy, truth, just, and merciful; we can trust in the triune God to never lie to us in His Word, never harm us, never to leave those who believe in Him. The more we know God and His salvation, the more we can be at peace in a restless world.

At Mt. Sinai, God declared in His law, "You shall have no other gods before Me" (Exodus 20:3). When Moses repeated the law forty years later he said, "Hear, O Israel: The Lord our God, the Lord is one!" (Deuteronomy 6:4). Only one God exists. He alone created the universe and sustains it. To trust in anyone or anything else is to worship an idol. Humans of every generation have "exchanged the truth of God for the lie, and worshipped and served the creature rather than the Creator" (Romans 1:25). When people do not worship our Creator, it is a great insult to the One who gave them life.

Malachi the prophet asked, "Have we not all one Father? Has not one God created us?" (Malachi 2:10). Yet, in the creation chapter of Moses he indicates that God is triune: "The Spirit of God was hovering over the face of the waters" (Genesis 1:2) and God said, "Let us make man in Our image" (Genesis 1:26). St. John wrote, "The Word was God. … All things were made through Him" (John 1:1,3).

Isaiah also proclaims the triune nature of God, when the Father says, "Behold! My Servant whom I uphold…I have put My Spirit upon Him; He will bring forth justice to the Gentiles" (Isaiah 42:1). In these words the Lord God speaks about His redeeming Servant and His Spirit. The Old Testament believers understood that God is triune. It was indicated by the Aaronic blessing, saying "The Lord bless you…" three times.

The clearest description of God's triune nature comes from the Son of God Himself, "Go therefore and make disciples of al the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit" (Matthew 28:19). Jesus spoke precisely. For if He had meant to speak of three gods, Jesus would have to say "in the names of." Jesus did not use the plural "names" because there is only one God, who exists as three Persons.

Since God's Word clearly teaches the triune nature of God, there should not have been any controversy over this teaching. However, Satan blinded many people to the truth of Scripture and led them to deny that Jesus was God, equal to the Father; deny that the Holy Spirit was God and He is only the Father's spiritual will; and deny that the Father created all things. Others accuse Christians of believing in three gods.

These attacks are the result of failing to believe that Scripture is true and clear,. And, except for the Holy Spirit's work in us, we would have joined them! For by nature we could not know these things about God. However, "let God be true but every man a liar" (Romans 3:4). We are to be like the Bereans, who studied Scripture to determine whether or not St. Paul had told them the truth. Jesus said, "If you believed Moses, you would believe Me; for he wrote about Me" (John 5:46). This summer, let God's Word guide you to know and believe the truths He reveals, even those truths we will never comprehend until we enter heaven through faith in Jesus.

Theodore G. Gullixson is the pastor of Grace Lutheran Church in Madison, Wisconsin.