@37818
I think we may be talking past one another when it comes to these terms.
I do insist that foundational doctrines (doctrines upon which we build other doctrines, essential doctrines, and such) be in the text of Scripture ("what is written").
I believe this for several readons, but the most important are:
1. I believe God accurately revealed essential doctrines in His Word, literally.
2. We can only test doctrine against "what is written". If we test a teaching against what we believe is taught then our understanding is ultimately the criteria.
BUT we, by necessity, also hold beliefs that are not in Scripture.
Theology develops over time, and it is always correct (in its development) to the time it was developed.
The Doctrine of the Trinity, for example, was developed to guard against false teachings that arose among Christians.
The teaching called Hypostatic Union was developed to correct errors along the same line.
Substitution Theory (Anselm) was developed to replace a form of Ransom Theory that was unbiblical.
We can talk theology.
My point of hypostatic union is not that it is a foundational doctrine. It is not. It does not have to be in the Bible. Christians can dismiss it. Obe dies not have to believe it to be saved.
BUT it DOES define "heresy" in regard to orthodox Christianity.
So when people disagree with it, it is up to them to prove their alternate position.
This applies to any developed theological doctrine.
I think it is proper to go back and reexamine doctrine.