Both Catholics and Orthodox deny the perspicuity and sufficiency of Scripture alone.
Scripture is divinely inspired, the New Testament authors wrote under the inspiration of the Holy Spirit.
We Reformed affirm Sola Scriptura (Scripture alone). This ensures the true gospel is not obscured. We recognize the perspicuity and total sufficiency of Scripture. Scripture is the highest standard of authority, and the only inerrant one.
By denying the gospel of salvation by grace alone, through faith alone, in Christ alone, for the glory of God alone, according to Scripture alone, the Catholic and Orthodox are in grave error.
The only way the true gospel is preserved and protected is by the principle of Sola Scriptura.
It ensures that our doctrine is based on God’s Word, and not on the man made traditions and not on Catholic or Orthodox magisteriums (papal pronouncements, decrees from various councils – such as the ecumenical councils, the beliefs of so-called Church Fathers, etc). The Catholic Magisterium asserts infallibility as a teaching authority. Catholics and Orthodox place man made traditions, and the teachings of their respective magisteriums, on the same level of authority as Scripture.
The authority structures, in the Catholic and Orthodox churches, are highly problematic, and riddled with outright heresies.
The ONLY remedy for this doctrinal madness is to affirm Scripture Alone as the sole authority for defining doctrine.
Catholic and Orthodox apologists are skilled in fallacious reasoning. Most of them are unable to discern the truth, and to embrace the true gospel, because these things can only be conveyed spiritually. The truths of Scripture are not accessible to anyone who is not born again (regenerated).
Applying the metric of Sola Scriptura to the Catholic and Orthodox churches, we find they are in fact false churches with a distorted and unbiblical gospel, a false gospel. This renders them as apostate entities. Without the anchor of Sola Scriptura, churches will descend into heresy and blasphemy against God. All of their rich vestments, smells and bells, mean nothing if one isn’t born again (regenerated). I believe these two churches have members who are born again, but sadly the vast majority are unconverted.
Even in the Reformed church, we have goats and sheep together. The true church isn’t an institutional church like the Catholic or Orthodox. Rather, it is the invisible church, made up of the regenerated from all churches, which is biblical. The born again church members were chosen by God, and they are given the twin gifts of sincere repentance and belief in the true gospel.
A select number of members of the Catholic and Orthodox churches are born again (regenerated), but the sad truth is that the vast majority of people in these churches will die in their sins and go to hell, apart from Christ.
All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work.
2 Timothy 3:16-17
I have applied all these things to myself and Apollos for your benefit, brothers, that you may learn by us not to go beyond what is written, that none of you may be puffed up in favor of one against another.
1 Corinthians 4:6
And how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus.
2 Timothy 3:15
And we also thank God constantly for this, that when you received the word of God, which you heard from us, you accepted it not as the word of men but as what it really is, the word of God, which is at work in you believers.
1 Thessalonians 2:13
For the word of God is living and active, sharper than any two-edged sword, piercing to the division of soul and of spirit, of joints and of marrow, and discerning the thoughts and intentions of the heart.
Hebrews 4:12
See to it that no one takes you captive by philosophy and empty deceit, according to human tradition, according to the elemental spirits of the world, and not according to Christ.
Colossians 2:8
Thus making void the word of God by your tradition that you have handed down. And many such things you do.
Mark 7:13
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