When defining doctrine, we Reformed affirm Sola Scriptura (Scripture Alone) as our highest authority. It restricts us from tainting our interpretation of Scripture by adding extraneous sources of doctrine.
Roman Catholics affirm Sola Ecclesia (Church Alone) contains the dual authorities of tradition and the magisterium (teaching authority). Scripture, tradition, and the magisterium are all equal in authority in the Roman Catholic church.
The Word of God should have a place of preeminence and singular authority.
By placing other things on par with Scripture, Roman Catholics get doctrine which is merely the fallible traditions of men, and as a result, much of their doctrines are false.
By applying Sola Scriptura to biblical exegesis we produce what is known as Reformed theology. Reformed theology alone has purity of doctrine, and infallible interpretation while one is being guided by the Holy Spirit. The Holy Spirit leads us into all truth. Roman Catholics will not arrive at Reformed theology, because they place tradition and their magisterium on the same level as Scripture. This results in eisegesis and much doctrine that is heretical.
Sola Scriptura is absolutely essential to preserving the biblical gospel. It is a critically important principle. It ensures we are following the right path of interpretation, and that our doctrine is absolutely biblical.
Historically, when churches have abandoned the principle of Sola Scriptura, they quickly descend into all manner of heresies and blasphemies.
The true gospel of Christ has been obscured and altered in the Roman Catholic church throughout the ages.
We thank God for raising up His Reformation of the Church.
The truest expression of right doctrine is found solely in Reformed churches.
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