Kevin has a question about the principle of first mention. Here is quote he sent that summarizes this approach to Scripture. The post I took it from can be found here.
“The law of first mention” is another most important principle involved in the Scriptures. What is meant by it is that the first mention of any fundamental word or institution usually presents the general conception of the subject and its use throughout Scriptures.
As an illustration of this law, I need only to call attention to the sacrifices that were required by the Lord from Cain and Abel. The very fundamental teaching concerning atonement for sin, with all its implications, is found in these sacrifices, as recorded in Genesis 4. Once more, the promise and the covenant which God made with Abraham (Gen. 12:1-3) constitute the bold outline of all that is involved in the divine plan which runs through the Scriptures. It becomes therefore of paramount importance that one study words, doctrines, and institutions in their original, initial mention.
I don’t put much stock in this for several reasons. First of all, the Scripture isn’t one book but a collection of books—so we don’t always know when something is “first mentioned.” For example, most people think Job was a contemporary of Abraham so the book of Job was in all likelihood written before Genesis. But that’s not an absolute certainty. The problem is if you’re going to adopt a FM approach, it’s incumbent that you know which books were written when so you know when something is FM.
But even if you work with a modified FM approach (like the first time a writer mentions something in their book/writing), it still doesn’t seem to hold up. For example, God is FM in Genesis as the One who creates heaven and earth. To me, that’s a decent principle to build around in understanding God. However, the Spirit is mentioned as “hovering over the waters,” (Genesis 1:2). Not so helpful.
Finally, I think most people would agree that the Scripture is a progressive revelation of God and His will for us. Therefore, things that are FM (like the Spirit), are developed tremendously in later Scriptures. Another example would be Jesus. Whether you understand the first allusion to Him to be Genesis 3:15, Genesis 2:24 (see Ephesians 5:31-32), or Genesis 1:26, it doesn’t matter—these are just seeds that grow into something marvelous throughout the remainder of Scripture.
Let me conclude by saying something positive about FM. There are times when I think it is significant. There are occasions when an writer introduces something and he does what we sometimes do—he defines it or at least presents it as he’ll be using it. For example, John’s presentation of Jesus in John 1:1-5 or his mention of the time element in Revelation 1:1,3, seem to fit in this category.
The bottom line to me is whether we like it or not, interpreting the Scriptures isn’t as easy as FM suggests. So when you try to take a shortcut like applying FM indiscriminately, it will bite you—and usually sooner rather than later.