I have been teaching theology now for over ten years. Teaching theology carries the burden of not only education, but one of correction. When it comes to heresies about the doctrine of the Trinity, there are two that stand out more than any other as being common among average Christians: subordinationalism and modalism. I will talk about modalism soon, but here I want to devote our time to subordinationalism.
We need to be careful as subordinationalism comes in two varieties, one orthodox and the other heretical. The orthodox version is called “functional subordinationalism,” while the unorthodox version is called “ontological subordinationalism.”
To subordinate something is to distinguish and lessen the value of that which is subordinated. The word “ontological” comes from the Greek, ontos meaning “essence,” “stuff,” or “substance.” So, Ontological Subordinationalism is to lessen the value of the substance. When it comes to the doctrine of God, Ontological Subordinationalism is the belief that there is a hierarchal subordination among the members of the Trinity in their essence.
For example, many people think that God the Father is the greatest and most powerful among the members of the Trinity. Christ comes in second and the Holy Spirit third. In order to do this, the Ontological Subordinationalist must distinguish between the members of the Trinity in their essence. Orthodox Christianity finds this heretical due to the fact that the Trinity is united in essence. Each member of the Trinity, though distinct in person, shares in the same substance. This sharing makes it impossible for any member to be less in any way in their essence. God the Father, God the Son, and God the Holy Spirit are all equal in essential power, authority, and dignity. There cannot be one that is subordinate to the other in their essence since this would divide the essence making three Gods. The Bible is clear that God is one in essence (Deut. 6:4; 1 Tim. 2:5), but three in person. Therefore, the Father is not more powerful than the Son, nor the Son more powerful than the Holy Spirit. All three are equal and eternal.
While orthodoxy does not allow for any hierarchy in the essence of the members of the Trinity, it does allow for a hierarchy in function or role among the members of the Trinity. Jesus tells us in John 14:28 that his Father is greater than he is. The greatness of which he speaks is tied to Christ’s role as redeemer and, possibly, as Son. While on the earth Christ submitted to the Father in everything in order to qualify to be the representative of mankind on the cross. The same is true of the Holy Spirit as he is sent by the Father and the Son and is in submission to their guidance (John 16:13-15).
One may ask how it is that one can be subordinate in role yet equal in essence. Yet we have many examples to which we can compare this relationship. While a king enjoys a role or function that is greater than his subject, the essential humanity of the both is equal. An officer who pulls you over for a traffic ticket has greater authority and power than you, yet his essential being is no greater. In the marital relationship (for those who hold a complementarian theology), the husband is the head of the wife, but they share equal value and dignity before God. Among the members of the Trinity, at least for the purpose of redemption, their is a functional hierarchy, even though there is not an ontological hierarchy. There is legitimate disagreement throughout church history about whether this functional hierarchy is temporary or eternal, but we wont go there now.
Any time we make Christ or the Holy Spirit a lesser God than the Father, we have fallen into the heresy of Ontological Subordinationalism. It is important for us to understand that there is one God who eternally exists in three persons, all of which are fully God, all of which are equal.