Both Judaism and Catholic Christianity teach that salvation comes from a combination of faith in God plus good works on earth.
By contrast, Protestant Christianity teaches that "faith alone" will save you.
Likewise, Judaism and Catholic Christianity teach that religious authority come from a combination of scripture and tradition.
Protestant Christianity teaches that the "bible alone" is the sole source of authority.
Protestant Christianity teaches that the “bible alone” is the sole source of authority.
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Where in the Bible is that “bedrock” truth stated?
With no living Apostle the writings The Holy Spirit inspired from them IS THE ONLY reliable source of authority. The traditions of men is exactly one of the pins upon which JESUS condemned the Pharisees.