What are two major and defining differences between Eastern Orthodoxy, Roman Catholicism, and Protestantism?

Question

Can you also explain the differences?

Answer 1

Here's one difference, among many: Neither Eastern Orthodoxy nor Protestantism accepts the authority of the Roman Catholic Pope.

Of course, a doctoral dissertation could be written on this question and not even begin to cover all the theological bases.

Answer 2

The one single Major difference is the authority of the Pope vs. the authority of Scripture.

Everything else falls under that.

Pastor Art

Answer 3

The major difference is who/what they consider to be the final authority on Christian doctrine.