Book 4
The Pss. in this book, as in that which follows, are mostly of comparatively late date, and suitable for use in the worship of the sanctuary.
The two books seem to have been conjoined at one time, and to have formed the third great division of the Psalter. In the 17 Pss. of Book 4 several smaller groups or collections are to be distinguished. Psalms 93, 95-100 are called the 'theocratic' Pss., because they celebrate God as King, finding in the restoration of Israel from Babylon the evidence of His rule over the world. These Pss. are probably to be dated soon after that event, when it was still the one thought in men's minds. Psalms 90, 91, 94, 102 probably belong to the exile, as their language suggests such a time of national humiliation and sorrow. Psalms 103, 104 go together, and are probably by one author, who belonged to the period of the return. Psalms 105, 106 form a pair of about the same date. The whole book is 'Jehovistic' in its use of the divine name.
The Pss. of the fourth book may be classified thus, the divisions necessarily overlapping one another: (a) Penitential Psalms 90, 91, 94, 102; (b) Pss. of Thanksgiving, 92, 93, 95-100, 103-106; (c) National Psalms, 94, 97, 99, 102, 105, 106; (d) Historical Psalms, 105, 106; (e) a Gnomic Psalms, 101.
Most of the Pss. in this book are anonymous, but Psalms 101, 103 are ascribed by their titles to David. LXX, however, also gives as Davidic Psalms 91, 93-99, 101, 103, 104.
There are definite references to the Temple worship in several of these Pss., indicating that the sacred bunding was restored to permit of the sacrifices being offered and public worship performed. The musical service was rendered with instrumental accompaniments (Psalms 98:5-6); the people were called upon to join in praise (Psalms 95:1; Psalms 96:1; Psalms 98:1; Psalms 98:4) and kneel in prayer (Psalms 95:6); offerings were to be made in the courts of he Temple (Psalms 96:8).
The Messianic hope appears in this book in the form of an expectation of Jehovah's coming in judgment. This was strengthened, if not wholly suggested, by the restoration from captivity, in which the pious Israelites saw the beginning of that coming. The people were led to look for a still greater day when their enemies would be finally overthrown, and the faith of those, who had trusted in God would be completely justified (see Psalms 96-98).
This famous Ps. (the 'Jubilate,' 'Old Hundredth') does not give God the title of King, but its contents are otherwise so similar to those of the previous 'theocratic' Pss. that it is naturally grouped along with them both as to subject and date. It calls the world to worship God (Psalms 100:1-2), describes Him as the Creator and Shepherd of His people (Psalms 100:3), points to the second Temple as the seat of His service (Psalms 100:4), and closes with an ascription of praise which was often repeated in post-exilic worship (Psalms 100:5).