What are the primary differences between Catholicism and Protestantism?
In an easy to digest manner, please.
OK. The first difference was in the theology of Martin Luther. The Church preached that man is a creature who is by nature good, but who, by a fault, renders his reasoning faulty, and does bad things — but that the fault can be healed, and right reason
recta ratio re-established, and man is restored to his essential and intrinsic goodness. Luther believed that man
is sin, that he is intrinsically and by nature a sinful thing.
Luther could not reconcile himself to the Church's view of man as good, and so broke with the Church. To do so, he argued that Scripture alone is the source of authority, and not Tradition (the Church's practices based on the interpretation of Scripture).
Luther, in rejecting the authority of the Church's tradition, nevertheless asserted the authority of his own interpretation of Scripture as sufficient for him to establish his own tradition. Basically the Church says "this is the way to think about 'X', and Luther said, "No, this is the way ... "
The row over indulgences, the public argument, was subsequent and shaped by this theology — there is no point in praying for the dead, because one cannot intercede with God and plead for mercy on their behalf. The Church argues that Jesus intercedes with God for us, He calls us 'friends' and asks His Father to forgive any offences by His friends. The Church believes that following Jesus' example, we should forgive 'those who trespass against us' and ask the Father to do the same.
So we get the "95 Theses" — Luther's rejection of the practice of indulgences because God alone saves, and man can have no say nor play any part in the matter.
Once Luther split with the Church, he opened the way for others to split also. So after him we have Zwingli, Calvin, et al. They disagreed amongst themselves on this point and that, but all agreed that:
1 — Man is a creature of sin.
2 — God saves whom He chooses, and damns who He chooses, and there's bugger all we can do or say about it.
3 — We are not perfected, rather our imperfection is politely ignored.
4 — All men are priests because the church is nothing but the collective name of a group of people who share a common belief.
5 — There is nothing man can do towards his own salvation. Church practice is just empty ritual — traditions are empty words and gestures.
The Catholic Church refutes all five points.
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The Scripture alone
sola scriptura debate did not stop the new denominations telling their followers what to believe and how to behave.
Only later, after the Enlightenment, did the idea develop into the notion of personal piety, that one's own interpretation of Scripture, as an infallible and inviolate process.
Thomas