Visiting the theology forums is an interesting place. But when a person cannot tell the difference between versions of truth, that does not necessarily imply all of the interpretations are false. The scripture would have to read something like:
"But there were also false prophets among the people, even as there will be false teachers among you who are also incapable of teaching the truth too..."
But to make the claim it does as a condition that exists within Christianity itself, is a proof that the word of God is being truthful. To be sure about the state of Christianity, it is clearly evident that people do not see, "till we all come to the unity of the faith and of the knowledge of the Son of God, to a perfect man, to the measure of the stature of the fullness of Christ" (Eph 4:13)
And the people certainly don't see this:
"No more shall every man teach his neighbor, and every man his brother, saying, 'Know the Lord,' for they all shall know Me, from the least of them to the greatest of them, says the Lord. For I will forgive their iniquity, and their sin I will remember no more." (Jer 31:34)
Also all people have religious viewpoints which share some common ground based on morality and ethics which include Atheists. And all including Atheists are arguing about having primacy. To whom has been given guidance by that intial cause which created the universe? That is a matter of faith in something greater than the self. Even though everyone seems to have different answers, does that mean it's impossible for any people to be given THE truth?
"Who has believed our report? And to whom has the arm of the Lord been revealed? For He shall grow up before Him as a tender plant, And as a root out of dry ground. He has no form or comeliness; And when we see Him, There is no beauty that we should desire Him. He is despised and rejected by men, A Man of sorrows and acquainted with grief. And we hid, as it were, our faces from Him; He was despised, and we did not esteem Him." (Is 53)