The Fruit of Heresy Is More Heresy

One fruit of heresy is more heresy. Catholic apologists have for some time--decades, at least--been noting that the doctrine of the Trinity is not found in the Bible. By this, what is largely meant is that neither the word "Trinity" nor the understanding of the doctrine is to be found in the Bible alone: the Bible certainly points to it, supports it (and does not contradict it), and this is a "right reading" of the Bible: but it is not self-evident from the Bible without the benefit of either hindsight or holy guidance. Now, as a Catholic, I do (or at least should!) read the Bible in the light of guidance from the Holy Spirit speaking through the Church and Tradition. Many Protestant exegetes would contend that we should of course consider guidance form the Church Fathers and maybe even some early councils, but these are no infallible (the Catholic or Orthodox might agree with the former but not the latter assessment).

Thus, it comes as no surprise that some Protestant (or even pot-Protestant) sects end up rejecting even what may be called "Mere Christianity" or "Christian orthodoxy": some things which Protestants take for granted as being supported by Sola Sciptura had to be uncovered and developed over centuries.

The doctrine of the Trinity is one such thing. The idea of three distinct persons being one God, all coequal, coeternal, of one substance and of one being without confusion developed over several centuries. It makes the most "sense" out of the "data" (e.g. what has been revealed to us), but it had to develop, often by way of negation (e.g. by rejecting and responding to incorrect interpretations of what we find in the Scriptures). Thus, the Church had to contend with modalism on the one side (Father, Son, and Holy Spirit are not different persons but instead different "modes" of existence or revelation of the one God) and Arianism soon after on the other (the Son and the Holy Spirit are not God in the fullest sense, not coequal or coeternal with God the Father).

While I reject the theology of the Oneness movement, I acknowledge that it is a very logical result of embracing Sola Scriptura an rejecting all outside/historical interpretations of Scripture (excepting of course the local Oneness pastor's, of course). It is also, alas, looking to become the next big Challenge for the Church to confront from within Christianity.