What is meant by calling the Bible the inspired Word of God?
By biblical inspiration we mean that God so positively influenced the human authors of the different books in the Bible as to make those authors His instruments for committing to writing, each in his own contemporary style, precisely what God wanted to be written. God, therefore, is the principal Author of the books, the human agents only the secondary and instrumental authors. Of each of the books we can say: "Thus saith the Lord", knowing it to contain the Word of God.
Are inspiration and revelation one and the same thing?
Not necessarily; for a biblical writer may have been inspired by God to commit to writing things naturally known to him and not needing to be revealed to him. On the other hand, it could be that here and there in an author's inspired writings events may be described which could be due only to God's direct intervention or doctrines may be taught which could have been made known to him only by divine revelation. The Second Vatican Council, in its "Constitution on Divine Revelation", n.II (Nov. 18, 1965) said: "Since everything asserted by the inspired authors must be held to be asserted by the Holy Spirit, it follows that the books of Holy Scripture must be acknowledged as teaching firmly, faithfully and without error that truth which God wanted put into the sacred writings for the sake of our salvation." We have to ask ourselves, therefore, what each of the inspired human authors intended to assert for the sake of our religious welfare, whatever the literary forms he might use in which to do so; and, above all, where the Old Testament is concerned, we must remember that God manifested His plan for us only partially and progressively as a preparation for the coming of the fulness of the truth in Christ, the very Word of God made flesh in the Incarnation and put before us in the writings of the New Testament.
The Faith of Israel, Questions 18-19 from Radio Replies Volume V Copyright © 1972 (by Rev. Dr. Leslie Rumble, M.S.C. and Rev. Charles Mortimer Carty).
