The division of the books of Psalms is one of the best proofs of the divine inspiration of the Bible. It would have been impossible for man to have originated the plan on which the Psalms as a whole are classified, whether into distinct books, or into an orderly series within those books. The collector and editor might have been Ezra, but God is the author.
The Jews regarded the Psalms as being divided into five books by divine arrangement, ending respectively with Psalms 41, 72, 89, 106, and 150. They also considered each book to correspond with the separate books of the Pentateuch, having the same distinguishing characteristics. Let us trace the parallelism.
The first book of Psalms (1-41) stands in the same relation to the whole collection that Genesis does to the Bible, both books being introductory and unfolding the counsels of God to this earth.
The second book (42-72) brings in God as Redeemer; hence the future blessing and redemption of the people on the ground of sovereign grace is the lesson here, as it is in Exodus.
In the third book (73-89) we have God made known as Sanctifier, and the whole nation set apart for God. The “sanctuary” and the “house” characterize these 17 psalms throughout, as they do Leviticus.
The fourth book (90-106) commences with what has been termed “the funeral psalm of the wilderness” — Psalm 90. Here too we have the patriarchal title “God Almighty,” faith’s resource in wilderness circumstances, and “Most High” the millennial title, so as to sustain the hopes of the pilgrim journeying home. The frailty and mortality of man is solemnly chanted in the opening of this new series of 17 psalms. But we have also the righteous ground unfolded in the death of the Messiah, and the glory and eternity of His being (Psa. 102), on which God will yet set His people in Canaan blessing, after the truths of death and resurrection have been practically learned. These are the very truths and characteristics of the fourth book of Scripture — Numbers.
The fifth book (107-150) is a book of review, a book in which the moral element largely prevails. Here God in His character, ways, and works is unfolded in sublime and rapturous strains. The correspondence to Deuteronomy is not difficult to perceive.
Notice that the first, second, and third books of psalms end with the words, “Amen, and Amen;” while the fourth and fifth close with a “Hallelujah,” or “Praise ye the Lord.” The expressive note attached to the second book (the 72nd psalm), “The prayers of David, the son of Jesse, are ended,” was probably the work of the inspired compiler. What more could be desired? Immanuel’s land is filled with glory and the praise of the once despised Nazarene, and the Man of sorrows engages the heart and tongue of the millennial earth, for “daily shall He be praised.” The last five psalms each begin with a “Hallelujah,” and also close with it, while the last of the five is a “Hallelujah psalm” throughout.