As a Catholic, I try to suppress the urge to tell to our Evangelical brethren: «We told you so». This is not a Christ-like attitude like but it’s the truth. A brief short with my broken English:
Luther tried to establish his authority over the Pope’s. How could he do that? He was only a monk and the Pope was (theoretically) the successor of Peter. He found a way: the Bible is the highest authority and I (Luther) am right because I am more faithful to the Bible than the Pope. He opened a can of worms. Because his reasoning could be replicated ad infinitum. Suddenly, everybody thought he was more faithful to the Bible than the neighbor.
This is why there is only one Catholic church, 8 Eastern churches, 12 Orthodox churches and 30 thousand Protestant churches. 30 thousand! I kid you not. Luther said that everybody could interpret the Bible, helped by the Holy Spirit. The Holy Spirit must have 30 thousand different personalities (a case of extreme multiple personality disorder, no doubt about it)
Unlike the Qur’an, which is the Word of God and hence perfect, the Bible is the word of writers inspired by God (for example, the books of Isaiah and Baruch are written by Baruch, the scribe). As humans, the writers introduced mistakes and biases, but the original message (the inspiration coming from God) was right. I see like a perfect sign telling «Smoking is not allowed» that you see through an imperfect glass. Maybe the shape of the letters is not perfect when you see them through an imperfect glass, but the message can be read. Maybe the cosmology of the Bible reflects the ignorance of his writers, but the salvation message can be read.
The important thing of Christianity is not the Bible (we are not Muslim), it is the message of salvation brought by Jesus, which includes the fact that Jesus is our Savior. The message was delivered to the apostles and the Church in an oral way (Jesus wrote nothing). The biblical books were not written until 90 AD and, even then, there were isolated books in the middle of other religious literature. The Bible as we know it was fixed by the Catholic Church at the councils of Hippo (393 AD) and Carthage (397, 419). They decided which books were included in the Bible and which books were excluded in the Bible.
So for 400 years, Christian people had no Bible. Weren’t they Christians? Wasn’t the apostle Paul Christian because he had no Bible? No, because the important thing is not the text of the Bible but the message of salvation written in it, and this message was delivered in other ways (in oral way, for example) through the Church. Jesus founded a Church, He did not found a Bible. He said the message to his disciples in an oral way. He did not wrote a letter. The Bible is only the best way to have these message that has been delivered by other channels (the tradition of the Church). For example, the story of Lucifer as a fallen angel is not in the Bible. It is really sad to see our Evangelical brethren commit the mistake of Bibliolatry, which goes against history and common sense. First, it was the Church and the Church begat the Bible and not the other way around.