Two words:
Prove it.
Protestantism (16th Century)
Protestant groups display a wide variety of different doctrines. However, virtually all claim to believe in the teachings of sola scriptura (”by Scripture alone”—the idea that we must use only the Bible when forming our theology) and sola fide (”by faith alone”— the idea that we are justified by faith only).
The great diversity of Protestant doctrines stems from the doctrine of private judgment, which denies the infallible authority of the Church and claims that each individual is to interpret Scripture for himself. This idea is rejected in 2 Peter 1:20, where we are told the first rule of Bible interpretation: “First of all you must understand this, that no prophecy of Scripture is a matter of one’s own interpretation.” A significant feature of this heresy is the attempt to pit the Church “against” the Bible, denying that the magisterium has any infallible authority to teach and interpret Scripture.
The doctrine of private judgment has resulted in an enormous number of different denominations. According to The Christian Sourcebook, there are approximately 20-30,000 denominations, with 270 new ones being formed each year. Virtually all of these are Protestant.
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