When we examine the New Testament doctrine of God, we are quickly confronted with a paradox. The New Testament affirms the Old Testament doctrine that there is One God, and only God is to be worshipped. At the same time, we see three divine Persons who enjoy interpersonal relations and are all considered worth of worship: the Father, the Son, and the Holy Spirit. This paradox is resolved through the doctrine of the Trinity.
Throughout history, people have forgotten that God is our Creator, and it is perfectly reasonable that we are not able to comprehend Him. However, the witness of Scripture is that in some way we can know God, indeed, that in some way we ourselves are in the very image of God. While perilous, we recall:
It is the glory of God to conceal things,
but the glory of kings is to search things out. Proverbs 25:2
Nevertheless, we must conduct this search with humility, bearing in mind that what we know of God is limited by what He has chosen to reveal of Himself.
The easiest way to resolve the paradox of the Trinity is to deny it in one form or another. Some, following the 4th century arch-heretic Arius, insist that only the Father is rightly called God. By this view, the Son is some sort of created being, perhaps an angel. Arius allowed the Son to be worshipped as a lesser god, but some modern Arians, such as the Jehovah’s Witnesses, seem to completely forbid the worship of the Son. The Council of Nicea and the Council of Constantinople condemned this false doctrine.
Somewhat along Arian lines, some people view the three Persons of the Trinity as separate beings, joined together by their love for one another. By this view, the term “God” is essentially an “office” held by these three beings. Some have gone so far as to assert that each of the Persons of the Trinity has a separate “body”, albeit not physical, but made of “spirit stuff”, whatever that phrase means! Yet it is difficult to see how these three beings are not three gods, emptying the assertions of Scripture that there is one God of their meaning. Furthermore, where did these three gods come from? Why three? How do we account for passages where the Father is called “God”, in contradistinction to the Son and the Holy Spirit? This “three gods” theory simply does not account for all the biblical data.
A different tact is to agree with Scripture that there is only one God, but to argue that the three Persons aspect is just an illusion. Perhaps God is changing, and the different Persons are just different modes of operation for God? In the 2nd century, Sabellius claimed that God manifested Himself as “Father” under the Old Testament, as “Son” during the life of Christ, and as the “Holy Spirit” during the present Church age. Yet how can one account for the statements like:
And now, Father, glorify me in your own presence with the glory that I had with you before the world existed. John 17:5
So this “Oneness” theory also fails to account for all the Biblical data.
Perhaps the earliest theological exposition of the doctrine of the Trinity was by the lawyer Tertullian, in his polemical essay Against Praxeas
This was Tertullian’s polemic against “Praxeas”, a Oneness teacher in Rome, who had also opposed the Montanists. Now the Montanists were a charismatic group, and some of their prophets were quite out of line, but it seems that much of the opposition to them was because the prophets were challenging the hierarchy forming in the church, and calling for purity. Anyway, Tertullian, himself a Montanist, wrote, “Thus Praxeas at Rome managed two pieces of the devil’s business: he drove out prophecy and introduced heresy: he put to flight the Paraclete and crucified the Father.” Tertullian’s writings, in Latin, largely defined the doctrine of the Trinity in the western (Latin-speaking) portion of the Church, during the days of Roman Europe.
The western Church has always leaned toward emphasizing the Oneness of God. In the eastern (Greek-speaking) portion of the Church, the chief concern was to “not confound the Persons” of God. It was in the East that the Arian heresy arose. Disputes about words, translation difficulties, and a stubborn, prideful unwillingness to listen and understand delayed resolving this paradox in the east, but eventually the Cappadocian Fathers (Basil the Great, his brother Gregory of Nyssa, and their friend Gregory of Nazianzus) formulated what is the historical theological understanding of the Trinity.
In Capadocian theology, it is understood that there is one God, and only one substance (ousia) of God. But there are three Persons (hypostases) within this one substance of God. Now when we talk about a Person of God, the substance of that Person is the totality of the substance of God. This it makes no sense to try to distinguish between the Persons of God based on their attributes. Attributes have to do with substance, so each Person has all the attribute of God. In a very real way, if I have known the Son, I have also known the Father. The Holy Spirit has been sent to dwell within the Church, yet it can be said that the Father and the Son dwell within us.
Nevertheless, there are three Persons. The Persons are distinguished by their relationships between each other. The Father is God ingenerate. The Son is called “begotten” in the Scripture. The Holy Spirit is sent by the Father through the Son. These distinctions are expressed in the Nicene Creed, as clarified by the Council of Constantinople in 381.
This leads us to our last point, that of subordination, or a hierarchy amongst the Persons. Origen, who first articulate the idea that the Son was eternally generated by the Father, insisted that the Son was a different substance (ousia) than the Father, and hence subordinate to the Father. As Nicene theology developed, this view was seen as defective. Since Father, Son, and Holy Spirit are all the same substance, this can not be the basis of any subordination. Nevertheless, the Scriptures do indicate that the Son is submitted to the Father; that submission is inherent in the very terminology of Father and Son. Thus, we see an economic subordination, where economic refers to an “ordering of a household”.
Some additional insights on the Trinity can be found in Jonathon Edwards’s essay on the Trinity: An Unpublished Essay on the Trinity Edwards can be hard to read, but he is profound. Edwards argues convincingly for the ontological necessity of the Son as eternally generated by the Father.