I disagree that Protestants "insist it is as wide as it can get." You're either confusing some present-day evangelical groups with Historical Protestants or you're wrongly recognizing the distinction between Protestant ecclesiology and soteriology. As a historical Protestant I readily affirm that they way is quite narrow.
The serpent used the same tactic in the Garden of Eden. He introduced doubt, and relativism. Eventually Eve was convinced that she and Adam will not die, as the serpent managed to get her to doubt God Himself! She was convinced that she was doing the "right" thing, and that becoming "just like gods" was okay, that disobeying, worse -- doubting God was reasonable.
What the serpent did was call into question God's own word ("Hath God said...?"). It was God's very own words which they disobeyed. That they rationalized, debated, weighed, and ultimately rejected God's clear words on the issue does not indicate a deficiency on the part of God or an inherent flaw in God's commands that requires Him to work through other means. God's word is God's word whether someone believes it and obeys it or not.
Why would God want 33,000 different denominations? Why owuld God want some Baptists to be Calivinsits (Reformed) and deny free will, while others don't? Why would he want Presbyterian Calvinists to be 'baby splashers" and Baptist Calivinists not? Why would he want Mormons, a pagan cult masquerading as "Christianity," to believe in three separate "gods," preach that God the Father used to be a mortal man, or that Jesus' borther is none other than Satan himself? Who would be better served with such religion: God or the devil? I think the answer is clear.
Again with the phoney-baloney 33,000 denominations garbage. Please, friend...enough with this tired, thoroughly refuted red herring.
The parallel argument is this: why would God want sin? Why would He allow sin to remain in the world? Who is better served by sin remaining in the world: God or the devil?
The answer is that while these things in and of themselves are not what God desires, He ordains them according to higher purposes which He does desire. A roundabout explanation of such a notion is given us in Rom 9:22-24. There is purpose in His allowing such things to be.
Christ is potentially everyone's Savior. But in order to come to Chirst, we need the correct path and that correct path is the correect, orthodox faith He dleivered, not anyone's fancy. Through Him, anyone can be saved, but not through false religions no matter how much they call on His name and on the Holy Script. Christ delivered the Faith and the authority to his Apostles and through the Apostolic sucession that faith and that authority continue unchanged. He did not give everyone a bible and said "just read it; it's perspicuous."
The Bereans knew where to look when looking to be sure they were not being led astray. Christ's Apostles delivered the Faith to the Church in their letters, which were recognized and understood to be their authoritative, inspired words. It's those very words you are forced to appeal to in arguing for the necessity of a specific institutional conduit through which those words must be delievered over time in the manner it sees fit.
You are right here, but Satan did not actually challenge God's Word; he challenged the authorized interpretation that Adam had given to Eve. The debate was about interpretation. Satan provided an alternative [non-authorized] and spiritualized intepretation about dying (i.e. dying to ignorance and blindness), and Eve followed the non-authorized interpretation.
-A8