Inspiration is defined as that work of the Holy Spirit of God upon the minds, souls, and bodies of the Scripture writers which makes their writings the record of a progressive divine revelation. When God determined to give to His creation the Self-revelation that we today call the Bible, He selected the Prophets of the Old Testament, and the Apostles of the New Testament, and through the agency of His indwelling Holy Spirit so over came the sin nature of these men that the words which He selected from the reservoir of the culture, education, experience, and personality of the man were His chosen words, and no others. This process of inspiration was two fold: Verbal, the very words that God selected were the very words that best revealed the mind and will of God to His creation. Thus, every word so inspired was in fact, the Word of God. Plenary, the collection of words that we call the Bible is, in its whole, the complete Word of God, without error or contradiction. The entire Bible, regardless of subject matter, is the infallible, unfailing, Revelation of God.
Now let's look at some of the various theories of inspiration that have been common in historic Christendom.
The Intuition or Natural Theory is held by the typical Modernist today, who believes that inspiration is merely a higher development of that natural insight into truth which all men posses to some degree. In other words, the Bible is merely a book by men with highly religious motivation, and is similar to a book about science written by men with highly scientific motivation. This theory, holding as it does that natural insight is the only source of religious truth, involves a serious self-contradiction; if the theory is true, then one man is inspired to utter that which another man is inspired to condemn. The Koran and the Bible cannot both be inspired Truth, as they contradict each other. This theory reduces moral and religious truth to the subjective - a matter of private opinion - having no objective reality apart from the opinions of men.
The Illumination or Mystical Theory regards inspiration as merely an intensifying and elevating of the religious perceptions of the believer, the same in kind, though greater in degree, as the illumination of every believer by the Holy Spirit. This position holds that the Bible is not the Word of God, but only contains the Word of God, and that not the writings, but only the writers were inspired. Of course, we must admit that there is an illumination of the mind of the believer by the Holy Spirit as we look into the Word of God, but this illumination only allows us to understand that which has already been written, and cannot impart new truth.
The Dictation or Mechanical Theory holds that inspiration consisted in such a possession of the minds and bodies of the Scripture writers by the Holy Spirit, that they became passive instruments, not participating in any way in the process of inspiration. This theory fails to explain the medical terms used by Luke, the military and sporting terms used by Paul, and the distinct differences between the books written by the various Old and New Testament writers. Of course, we must grant that there are instances when God's communications to mankind were in an audible voice, and took the form of spoken words, and that sometimes God commanded men to commit these words to writing for the edification of all men. However, the Dictation Theory would force this occasional event upon all of Scripture, quite apart from the evidence to the contrary.
The Dynamic or Conceptual Theory states that inspiration is not simply a natural, but also a supernatural fact, and that it is the immediate work of a personal God in the soul of man. This theory holds that the Scriptures contain a human as well as a divine element, so that while they present a body of divinely revealed truth, this truth is shaped in human molds and adapted to ordinary human intelligence, and is thus conceptual (the idea, or thought, or concept is inspired) rather than verbal (the very words are inspired) in its view of inspiration. This is the view held, unfortunately, by many fundamentalists today, and is the basis for the proliferation of the many English language translations of the Scriptures now on the market, each one trying to put into different words the inspired thought, or idea, or concept of the original, while glossing over or even ignoring the words inspired by God.
The Verbal and Formal Inspiration position believes that first of all the Holy Spirit worked in the Prophets of the Old Testament and the Apostles of the New Testament in such a way that the very words of God were selected from the vocabulary of the man, taking into account his culture, education, and experience, and that not only the very words, but also the forms of the words, such as noun, pronoun, verb, adverb, singular, plural, etc., were written at the prompting of the Holy Spirit. This view is the only one that can give us a completely inspired, inerrant, infallible, preserved Bible, as well as account for such statements as Paul saying that the very form of a word was inspired by God for a specific purpose as in Galatians 3:16, and Christ saying in Matthew 5:18 that not only was each word inspired, but every letter of every word was inspired. The Scriptures of the Old and New Testaments are the perfect mirror of the Lord Jesus Christ, which reflects Him and leads us to Him. Authority resides in the Scriptures just as it does in Him. Just as all authority is given to Christ (Matthew 28:18), the living Word, all authority is bound up in the Scriptures, the reflection of Him, the written Word of God.
Now comes the problem we face in fundamental circles today. What exactly was it that God inspired. Was it men? Was it manuscripts? Was it languages? One of the greatest failings of fundamentalism today is this confusion concerning the doctrine of inspiration. If you were to ask every independent, fundamental Baptist Pastor what it was that God inspired, most would reply "the original manuscripts." However, you can search the scriptures forever, and never find a reference to the "original manuscripts." But you will find, over and over again references to the "words" that God has spoken. God did not inspire men or manuscripts, He inspired words! God did not concern Himself with parchment, vellum, papyrus, and ink, but with words! It was, and still is, the words of God that are inspired. It makes absolutely no difference if those inspired words are written by the hand of Moses, Samuel, David, Daniel, Matthew, Mark, Luke, John, Paul, Peter, James, or if they were carefully copied by a copyist in his own handwriting, or if they are scrawled on the rest room wall! If they are the same words, they are God's words, and if they are God's words, they are inspired words!
Unfortunately many object to this view of Scripture for various reasons. Some say that factual errors in the Bible disprove this verbal and formal view of inspiration. Now we must ask, does the Bible contain factual errors? Yes, it does, but before you get out the tar and feathers, allow me to elaborate! The pious speeches made by Job's "comforters" contain factual errors. However, inspiration guarantees the accurate recording of these speeches, but not the truthfulness of the content. Satan said "Ye shall not surely die," in Genesis 3:4. That statement is a lie, but is accurately recorded by the Holy Spirit. The Bible speaks of "the four corners of the Earth" in Isaiah 11:12 and Revelation 7:1, apparently ignorant of the scientific fact that the earth is round. However, this so-called error is nothing more than using the language of appearance. We still say today that the sun rises and sets. However, we know that scientifically speaking, the sun neither rises nor sets, but it is the Earth that rotates upon its axis, producing the appearance of the sun rising and setting. Are we in error then to say that the sun rises and sets? No, the sun still appears to rise and set, and I for one will continue to enjoy watching the beauty of the swollen red sun setting in the Pacific Ocean, and even though I may be unscientific in my description of a sunset, it remains just as beautiful. Besides which, the Bible clearly teaches that the Earth is round in Isaiah 40:22. Also, we still describe our world as having four directions North, South, East, and West, or some combination thereof. Is it wrong to say that there are four primary directions (corners?), I don't think so.
So then, the honest reader will see that when viewed properly, the Bible is the inspired, inerrant, infallible, and all sufficient Word of God, totally worthy of our full trust and confidence in all matters of faith, practice, knowledge, and understanding, and is able to "make us wise unto salvation", as well as "lead us into all truth."