The orthodox view of the Trinity is that there is only one God and yet three different persons that make up that one God. At face value, this would appear to violate the law of noncontradiction. This law states that contradictory propositions cannot both be true in the same sense at the same time. Example: “It’s snowing outside” is either true or false. It can’t be both. I’m either married or I’m a bachelor. I can’t be a married bachelor. It’s nonsensical. 

How can God be only one and yet three at the same time and in the same sense? The answer: He can’t. 

God is not both three and only one in the same sense. He is only one in nature (or essence) but three in a different sense - in persons. Three persons in one nature is no more a contradiction than 1x1x1=1. While this is a mystery, it’s not a contradiction. 

What does the word Trinity mean? It means that God is a triunity. He is a plurality within a unity. God has a plurality of persons in the unity of essence. One way to think about it, there is only one “What” (essence) but there are three “Whos” (persons) in that one What. 

Personhood usually describes one who has a mind (intellect), will, and feelings. All three of these characteristics are revealed within all three members of the Trinity. 

Shema

Let’s start with an OT understanding of God’s essence or nature. The most important verse for ancient Jews, and central to their faith, was called the Shema. 

“Hear, O Israel: The Lord our God, the Lord is one. You shall love the Lord your God with all your heart and with all your soul and with all your might.” ‭‭Deuteronomy‬ ‭6‬:‭4‬-‭5‬ ‭ESV

This verse is so significant because at the time, ancient Jews were surrounded by Canaanite and Babylonian polytheism. The idea of one true Creator God (Isaiah 45:5) was a radical idea and what separated the Jews from the rest of the world. Jesus quotes the Shema in Mark 12:29 when the Jewish leaders ask him which is the most important commandment. 

“Jesus answered, “The most important is, ‘Hear, O Israel: The Lord our God, the Lord is one. And you shall love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’ The second is this: ‘You shall love your neighbor as yourself.’ There is no other commandment greater than these.”“ ‭‭Mark‬ ‭12‬:‭29‬-‭31‬ ‭ESV‬‬

The message doesn’t change. There is one God. Jesus proclaims that first you are to love the Lord with all your heart, soul, mind, and strength. Second, you’re to love your neighbor as yourself. In Paul’s first letter to Timothy, he teaches that there is one God, while recognizing that Jesus is this divine-human mediator between humans and God (1 Timothy 2:5-6). So who is this one God?

Yahweh

Yahweh (Hebrew) or Jehovah (English) was a special name that God gave for himself in the OT. It was revealed to Moses in Exodus 3:14 when he said, “I am who I am.” Yahweh is a special word reserved for the One true God. No other person or thing was to be worshiped or served (Exodus 20:5) and His name and glory were not to be given to another (Isaiah 42:8). 

Implications of monotheism

Because there is only one God, idolatry of any kind is considered evil. Worship of other gods robs the true God of the devotion and glory that He alone deserves. Jesus warns us that money can become an idol (Matthew 6:24). Paul warns us that greed, lust, and impurity can become idolatry (Ephesians 5:5, Colossians 3:5). Because there is only one God, He alone should be the ultimate object of our affection. He alone deserves our obedience. 

Loving God

The idea of loving God was a radical idea as well. In the Ancient Near East, gods were not to be loved, they were to be feared. Babylon was one of Israel’s most powerful ancient neighbors, and their belief was that the world was created when the chief Babylonian god, Marduk, battled an ancient sea monster, Tiamat. Marduk kills Tiamat and uses the creature's body to make heaven and earth. It’s an incredibly violent story. All of creation is born out of death and violence. 

Human beings were created as an afterthought—only after the other gods complained about their labor. Humanity’s purpose of existence is to “set the gods free” from the labors of their daily existence. Humans were slaves to the gods. So the common belief was that the heavens and earth were created out of violence and humans were to be slaves to the Gods.

Then comes along Israel who follows a God called Yahweh. Yahweh is the one Creator God who birthed everything out of love and beauty. And He created humans in His image, not to serve, but to co-rule the earth in partnership with Him. And He sought to have a loving relationship with His creation. This belief system was completely radical at the time, and quite frankly, still is today. 

Evidence for three distinct persons

We know that there is one God and we are to love Him and submit to His will. As the nature of God is revealed throughout scripture, the One God is eternally expressed in three persons. These three persons share the same divine nature but are different in role and relationship. They are unified but distinct. Anything true of God is true of the Father, Son, and Holy Spirit. 

As discussed earlier, personhood includes three basic elements: a mind, a will, and feelings. We’ll go through each person of the Trinity and look for evidence of these elements throughout Old and New Testaments.