We should see exactly what is meant by the perspicuity of Scripture. It means that no human interpreter needs come between the Scriptures and those to whom it comes. It is opposed to clericalism. This does not mean that men who place themselves with us under the Scriptures, and who are ordained of God for the preaching of the Word, cannot be of service to us in the better understanding of Scripture. The perspicuity of Scripture is perfectly consistent with the Protestant teaching with respect to the task of the preachers of the Word, but it is directed against the Roman Catholic notion that no ordinary member of the Church may interpret Scripture for himself directly. The doctrine should therefore be definitely maintained against Romanism.
Perspicuity does not mean that every portion is equally easy to be understood. It means that with ordinary intelligence any person can obtain, without the intervention of priests, the main point of the things he needs to know.
“Fundamentalism” has sometimes abused this doctrine. Under the slogan of going back to the Bible, it often ignores the great insight into the truth of the Bible that the Church has already obtained in the generations past. This insight has been deposited in the creeds of the church. He who ignores the creeds under the slogan of going to the Bible does despite to the Spirit who has led the church into all truth.
– Cornelius Van Til, An Introduction to Systematic Theology p.226-227