Excerpts from the Letter of St. Athanasius to
Marcellinus.
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Son, all the books of Scripture, both Old Testament and New, are inspired by God and useful for instruction, as it is written; but to those who really study it, the Psalter yields special treasure. Each book of the Bible has, of course, its own particular message: the Pentateuch, for example, tells of the beginning of the world, the doings of the patriarchs, the exodus of Israel from Egypt, the giving of the Law, and the ordering of the tabernacle and the priesthood.... Esdras (the story of Susanna ) [tells] the deliverance from exile, the return of the people, and the building of the temple and the city .... Each of these books, you see, is like a garden which grows one special kind of fruit; by contrast, the Psalter is a garden which, besides its special fruit, grows also some of those of all the rest...
My old friend made rather a point of this, that the things we find in the Psalms about the Savior are stated in the other books of Scripture too; he stressed the fact that one interpretation is common to them all, and that they have but one voice in the Holy Spirit.