Many people think that only the New Testament is relevant, that the Old Testament with its rules and symbolism was replaced or superseded. Yet New Testament writers quoted extensively from the Old Testament which they called Scripture, the Law and the Prophets, Psalms or Isaiah, often beginning the quote with an "it is written" or including a "says the Lord." Jesus used the phrase "it is written" a number of times in His struggle in the desert with the devil. And Christians today even as yesterday, need to meet the devil's temptations with the word of God. "It is written" and a "thus saith the Lord." If Christ came to "fulfill Scripture," then it would behoove us to study the Scripture to understand more clearly Christ's mission to this world (see Matthew 5:16 ff.).

The first five books of the Old Testament were referred to as The Law (of God or of Moses). The major and minor prophets of the Old Testament were referred to as the Prophets, with Psalms, and other books being referred to as well.  In fact, every book in the Old Testament is quoted somewhere in the New Testament.

The following texts were compiled from the Old and New Testament showing how the books of the Law of the Lord, the books by the Prophets and the Psalms were quoted or used extensively by those who had access to them, how the Scriptures came about, and what they are to be used for.