Christian theologians embrace divine simplicity because it is biblical. It also invites us to trust in His unity, share His sufficiency, and love all of Him. We cannot rank the divine persons; they are distinct from each other but not divided from each other. They are not three parts that add up to a single godhead. John Calvin understood the name God to be “the one simple essence, comprehending three persons.” In our chaos we can come to a God in whom, as the Athanasian Creed puts it, “the divinity of the Father, Son, and Holy Spirit is one, the glory equal, the majesty coeternal.” Such as the one is, so are the three. “None in this Trinity is before or after, none is greater or smaller” (arts. 6, 7, 25). We can trust one God in three equal, co-eternal persons.
One of the best questions we can ask is also the most challenging: “What is God?”[1] As the Church has searched Scripture for answers it has consistently used a surprising word to describe the divine Being: simplicity. God is simple—not in the sense of “easily understood” but as “being free from division into parts, and therefore from compositeness.”[2] God is one (Deut. 6:4); He is both unique and indivisible.
The word simplicity, like trinity, is not found in the Bible, but reformed confessions affirm that the doctrine is biblical. The Lutheran Augsburg Confession states that “there is one Divine Essence…which is God: eternal, without body, without parts” (art. 1). Dutch Reformed believers confess the same thing: “There is a single and simple spiritual being, whom we call God” (Belgic Confession, art. 1). In the Church of England divine simplicity is taught in the Thirty-nine Articles, “There is but one living and true God, everlasting, without body, parts, or passions” (art. 1). The Westminster Assembly—which convened to modify these articles but then chose to replace them—retained the exact language of Anglicanism (Westminster Shorter Catechism 2.1), as did English Baptists (London Baptist Confession, 2.1). These confessions draw on the testimony of church fathers like Augustine, medieval theologians like Aquinas, and reformers like Calvin, Melanchthon, and Zwingli.
Divine simplicity is firmly embedded in the reformed confessional tradition. If we understand simplicity, we may come to join the doctors of the church in treasuring this doctrine.
What Is Divine Simplicity?
When God revealed Himself to Moses at the burning bush He identified Himself as being—the “I am” (Ex. 3:14). Unlike everyone else, He is not from somewhere or the fruit of ancestors. He is not even a species within a genus. Instead, He is the God who is, “the ultimate principle and …category of all things.”[3] Herman Bavinck wrote, “God is the real, the true being, the fullness of being, the sum total of all reality and perfection, the totality of being, from which all other being owes its existence.”[4] God is truly “all and in all” (Col. 3:11). Drawing from texts like these, divine simplicity maintains that in God there is “no composition, no contradiction, no tension, no process.”[5]
No Composition
God is not a sum of parts, as we are, made up of body and soul, atoms and neurons, past, present, and future. God’s attributes do not add up to what He is. As a child I wore out a book that described a little boy’s attributes—quickness, loudness, bravery—that made him who he was. Here is the climax of the book: “Put it all together and you’ve got me!” That’s true for us. It is untrue for God. Each of God’s attributes is identical with Himself and His other perfections because each is infinite.