We also learn from history, as Jesus was an historical figure, as were the Roman prelates.
Scripture, Apostolic Tradition and history. There aren't any other sources.
Do you believe that Scripture is the ONLY source of our faith? If so, where does it say that in Scripture?
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So you are simply asserting something not found in Scripture ever.
Scripture is the only thing necessary for salvation and Christian maturity.
And when you assert something that is contrary to Scripture, as youve done, scripture judges that belief as false.