1. Autonomy.
Like the Roman Catholic doctrine, its final authority is each individual believer deciding for himself what is and is not biblical. “The result is subjectivism and relativism. The reformers’ appeal to ‘Scripture alone,’ however, was never intended to mean ‘me alone.’”
2. Unbiblical.
“Christ established his church with a structure of authority and gives to his church those who are specially appointed to the ministry of the word (Acts 6:2-4).” Disputes were settled by councils, as in Acts 15:6-29. Paul taught the Bereans as a group (Acts 17:1-11).
3. No resolution of differences.
Adherents of solo Scriptura are told that different interpretations can be resolved simply by an appeal to Scripture. “But how is the problem of differing interpretations to be resolved by an appeal to another interpretation? All appeals to Scripture are appeals to interpretations of Scripture. The only real question is: whose interpretation? … This is subjectivism and relativism run amuck.”
4. Historical problems.
If “solo” Scriptura were true, much of the ancient church had no standard of truth for many years, because copies of the Bible were very few and expensive then. The first books of the New Testament began to be copied ten years after Christ’s death, and was not completed until about 70 years later! “If the lone individual is to judge and evaluate everything by himself and for himself by measuring it against Scripture, as proponents of ‘solo’ Scriptura would have it, how would this have possibly worked in the first decades of the church before the New Testament was completed?”
5. Who determines the canon of Scripture?
“If one is going to claim that Scripture is the only authority whatsoever, it is legitimate to ask how we then define what is and is not ‘Scripture.’ … How would ‘solo’ Scriptura deal with a modern day Marcion … who claimed that the real New Testament includes only the books of Luke, Acts, Romans, and Revelation? He can’t appeal to the church, to history, or to tradition. A self-consistent adherent of ‘solo Scriptura’ would have no way to respond to such a view because … it is the right and duty of each individual Christian to determine the canonicity of each biblical book by and for himself.”
6. Who determines orthodoxy or heresy?
“The adoption of ‘solo’ Scriptura destroys the possibility of having any objective definition of what Christianity is and is not. ‘solo’ Scriptura destroys the very concepts of orthodoxy and heresy. If the authority of the ecumenical creeds is rejected, and if each individual believer is to determine all questions of doctrine by and for himself, then the definitions of orthodoxy and heresy are completely relative and subjective. One man judges the doctrine of the Trinity to be biblical. Another deems it unbiblical … The same is true with respect to every other doctrine. Each man defines Christianity as it seems right in his own eyes.”
7. The Bible did not just drop out of the sky.
“If ‘solo’ Scriptura were true, it should be possible to give untranslated ancient Hebrew and Greek manuscripts of biblical, apocryphal, and pseudepigraphal texts to some isolated tribe member somewhere on earth, and with no one’s assistance, that individual should be able to learn the Hebrew and Greek languages, read the various manuscripts, determine which of them are canonical, and then come to an orthodox understanding of the Christian faith.”