St Athanasius and the garden of delight

The introduction to St Athanasius' letter to Marcellinus points to the re-eminence of the book of Psalms in Scripture:

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 especial 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; The Triteuch [Joshua, Judges, and Ruth] describes the division of the inheritance, the acts of the judges, and the ancestry of David; Kings and Chronicles record the doings of the kings, Esdras [Ezra] the deliverance from exile, the return of the people, and the building of the temple and the city; the Prophets foretell the coming of the Saviour, put us in mind of the commandments, reprove transgressors, and for the Gentiles also have a special word.

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 those of all the rest.