I do not know about evangelical faith, but it is foundational for TRUE Christianity. There are some who like to call themselves Christian but are far from being Christian. Either the Bible is God's Word and is without error or it is not God's Word and is in error. God is Perfect and without error, his Word must also be without error or it is not from him. There are false teachers and false Christians ( who are really not Christian ) who embrace an idea of God but not the true nature of God, and therefore are diluted in their thinking and except falsehood.( Romans 1:18-32 ) These people have no fellowship with the one true God, and his people the Church. John 1:1-5 states that Jesus Christ is the Word made flesh and blood. Jesus Christ is without error and so is the Word that he became one with.
Now I'm not talking about the English Bibles that we have, but the Original Word in the Original language of Hebrew and Greek, of which we have over 5000 copies. More than any other ancient document of History. The Original Word has been well Preserved.