Yesterday I did my best to briefly summarize why Jesus must be God. Today, I want to do the same with the question, Why must God be a Trinity?
If we are honest, the Trinity seems, at best, a math problem or a religious puzzle to solve. At worst, it is a man-made construction not supported in the Scriptures, as many in history, and still today, have proposed. But before trying to figure out how God is one-yet-three and three-yet-one (and you won’t figure that out!), I suggest we ask why God must be a Trinity.
The easiest way to summarize the answer is this: God must be a Trinity if he is to be a God who is love. I have heard it said, “The Trinity is the good news that God is love.” God does not just love (a verb), though he does do that! But he is more than doing. God’s very essence is love (a noun). God can love because he is love—Father, Son, and Spirit, who exist in perfect loving relationship with each other. This loving community of persons are united in their being and purpose, yet diverse in their roles, responsibilities, and functions. The Trinity is a diverse unity of three. If God is merely one—monolithic, as it were—he can be many things. But he cannot be love. To be love and to love, by very definition, requires relationship with someone other than yourself. The alternative is called vanity.
Allah, the god of Islam, for example, can be many things, but he cannot be love. If love is not a god’s essence, it can be created and destroyed. If love is not a god’s essence, then something else must and will be. This is not good news.
If we reflect further on why God must be a Trinity, there are numerous applications:
- Human beings are made in God’s image. Thus to be human means we are communal beings designed to live in loving relationship with each other.
- Marriage between a man and a woman reflects the Trinity’s diverse unity. Man and woman become “one flesh,” are equal in their worth before God, and share a united purpose, yet they have different, complementary (not competing) roles and responsibilities.
- The church is to be a diverse unity of persons, who together have a common faith, identity, and mission, yet individually have differing gifts, roles, functions, and activities.
Ultimately, because God is a Trinity—because he is love—the Father can, out of his great love for us, send his Son to atone for our sin and appease his holy wrath. The Father pours out his wrath on his own Son on the cross. The Son completely satisfies God’s wrath, paying the debt we owe with his blood. And in his resurrection, he conquers death so that all who repent of their sin and trust in the Son, are welcomed by the Father into this loving, harmonious, diversity unity of three through his giving us his Spirit. Do you see what this is? It is a Family working in unity, with complementary roles, to rescue lost, rebel orphans and bring them into the Family.
And this is good news. For you, for me, and for the world.
Scriptures to consider: Genesis 1:1, 26-27; Psalm 110; Matthew 28:19-20; John 15-17 (esp. John 17); 1 Corinthians 12:4-6; Ephesians 4:1-7; 1 John 4:7-21