These greater groups rest, however, upon other smaller ones, some formally acknowledged, e.g. the so-called Psalms of Ascent or Pilgrim psalms (cxx.-cxxxiv.), the Psalms of David, Psalms of the Korahites (xlii.-xlix., etc.), Psalms of Asaph (lxxiii.-lxxxiii., etc.), and others not so obvious in a translation, e.g. the Hallelujah Psalms, cxi.-cxiii., cxlvi.-cl. These groups must often have enjoyed an independent reputation as groups, and even been invested with a certain canonical authority, for occasionally the same psalm appears in two different groups (xiv.=liii., xl. 13-17=lxx., cviii.=lvii. 7-11 +lx. 6-12). Such repetition proves that the final editors did not consider themselves at liberty to make any change within the groups. The principle of the arrangement of individual psalms within the group was probably not a scientific one: e.g. xxxiv. and xxxv. seem to be placed together for no other reason than that both refer to "the angel of Jehovah," xxxiv. 7, xxxv. 5. Sometimes a psalm has been wrongly divided into two (cf. xlii., xliii., originally one psalm) and occasionally two psalms have been united, usually for reasons that are transparent (so perhaps xix., the revelation in the heavens and the revelation in the Scriptures, and xxiv., the entrance of Jehovah into His temple, and the essential conditions for the entrance of man).

The original order of the groups themselves appears to have been dislocated. Whoever added the subscription to Psalm lxxii. can hardly have been aware of the eighteen psalms which, in the subsequent books of the Psalter, are ascribed to David; nor is it natural to suppose that the Asaphic (l.) and Korahitic psalms (xlii.-xlix.) stood in the second book when that subscription was written. It is not improbable that Psalms xlii.-l. originally belonged to the third book, along with the Asaphic group, lxxiii.-lxxxiii., and that lxxii. 20, "The prayers of David the son of Jesse are ended," was intended as the subscription of all the Davidic psalms that had then been collected (Book I, except Pss. i., ii., x., xxxiii., and book 2, Pss. li.-lxx.).[1] The first two books originally represented a Davidic hymn-book; they probably represent, as a whole, the oldest part of the Psalter. [Footnote 1: Psalms i. and ii. were placed at the beginning as prefatory to the whole Psalter. They deal with the two cardinal points of Judaism—the law and the Messianic hope. Psalms ix. and x. originally constituted one alphabetic psalm, and xxxiii. is ascribed to David in the Septuagint.]

The problem of the authorship of the Psalms is one of the thorniest in the Old Testament. One hundred psalms are ascribed to definite authors: one is ascribed to Moses (xc.), seventy-three to David, two to Solomon (lxxvii., cxxvii.); and yet there are not a few scholars who maintain that, so far from any psalm being Mosaic, or even Davidic, there is not a single pre-exilic psalm in the Psalter, and the less radical critics do not allow more than thirty or forty. The question must be settled entirely upon internal evidence, as the superscriptions, definite as they often are, are never demonstrably reliable, while some of them are plainly impossible. To begin with, doubt attaches to the meaning of the Hebrew preposition in the phrase, "Psalm of David." It is the same preposition as that rendered by for in the phrase, "For the chief musician," and as in this phrase authorship is out of the question, it may be seriously doubted whether it is implied in the phrase rendered "Psalm of David." This doubt is corroborated by the phrase, "Psalms of the sons of Korah." Plainly all the Korahites did not cooperate in the composition of the psalms so superscribed; and the most natural inference is that the phrase does not here designate authorship, but that the psalm is one of a collection in some sense belonging to or destined for the Korahitic guild of temple-singers. [1] In that case the phrase would have a liturgical sense, and the parallel phrase "of (or for) David," might have to be similarly explained. It must be confessed, however, that whatever the actual origin of the superscription, "of (or for) David," it certainly came to be regarded as implying authorship—the many historical notices in the superscriptions of Psalms li.-lx. are proof enough of that; and no other explanation is possible of the superscription "of Moses" in Psalm, xc (cf. Is. xxxviii. 9, the writing of Hezekiah). [Footnote 1: It is not absolutely impossible that the phrase might point to a collection composed by this guild, cf. "Moravian brethren." But the other supposition is more likely.]

In later times, then, authorship was plainly intended by the superscriptions. But it is quite certain that the superscriptions themselves are no original and integral parts of the psalms. In the Septuagint they occasionally differ from the Hebrew, assigning psalms that are anonymous in the Hebrew (xcv., cxxxvii.) to David, or to other authors (e.g., cxlvi.-cxlviii. to Haggai and Zechariah.) The ease with which psalms were, without warrant, ascribed to David may be seen from the Greek superscription to Psalm xcvi. "When the house [i.e. the temple] was being built after the captivity; a song of David": in other words, an admittedly post-exilic psalm is ascribed to David. The superscriptions were added probably long after the psalms, and there is no reason to suppose that the Hebrews were exempt from the uncritical methods and ideas which characterized the Greek translators. That they shared them is abundantly proved by the historical superscriptions. One at least (Ps. xxxiv.) in substituting the name of Abimelech (Gen. xx.) for Achish (1 Sam. xxi.) shows either ignorance or carelessness, and casts a very lurid light on the reliability of the superscriptions. The contents of other psalms are manifestly irreconcilable with the assumed authorship: Asaph, e.g., whom the Chronicles regards as a contemporary of David (1 Chron. xvi 7), laments in Psalms lxxiv., lxxix. the devastation of the temple, which was not at that time in existence. The principles on which the superscriptions were added were altogether superficial and uncritical. Psalm cxxvii. is ascribed to Solomon, chiefly because its opening verse speaks of the building of the house, which was understood to be the temple. So Psalm lxiii. is described as "a psalm of David when he was in the wilderness of Judah," simply on the strength of the words, "My soul thirsteth for thee in a dry and weary land where no water is"—words which are taken literally, though they were undoubtedly intended metaphorically. A parallel case is that of the psalm inserted in Jonah ii., obviously a church psalm whose figurative language has been too literally pressed.

Enough has been said to show that the superscriptions are later than the psalms themselves, and often, if not always, unreliable; we are therefore wholly dependent upon internal evidence, and the criteria for Davidic authorship must be sought outside the Psalter. The only absolutely undisputed poems of David's are the elegy over Saul and Jonathan in 2 Samuel i. and the lament over Abner (2 Sam. iii. 33, 34). There is no means of proving that 2 Samuel xxii. (=Ps. xviii.) and 2 Samuel xxiii. 1-7 are David's, as they are interpolated in a section of Samuel which is itself an interpolation (xxi.-xxiv.), interrupting as it does the continuity of 2 Samuel xx. and I Kings i. The data offered by the elegy are much too slender to enable us to decide whether any particular psalm is David's or not. Some have ventured to ascribe a dozen psalms or so to him on the strength of their peculiar vigour and originality, but obviously all such decisions must be altogether subjective. What is certain is that David was an accomplished musician (1 Sam. xvi. 18) and a great poet (2 Sam. i.), a man of the most varied experience, rich emotional nature and profound religious feeling, a devoted worshipper of Jehovah, and eager to build Him a temple; and it is not impossible that such a man may have written religious songs, but in the nature of the case it can never be proved that he wrote any of the songs in the Psalter. Psalm xviii. has been by many assigned to him with considerable confidence because of the support it is thought to receive from its appearance in a historical book; but besides the fact that this support, as we have seen, is slender, the psalm can hardly, at least in its present form, have come from David. The superscription assigns it to a later period in his life when he had been delivered from all his enemies; but at that time he could not have looked back over the past, stained by his great sin, with the complacency which marks the confession in vv. 20-24. Others have supposed that xxiv. 7-10, with its picture of the entrance of Jehovah through the "ancient gates," may well be his. It may be, if the gates are those of the city; but if, as is more probable, they are the temple gates, then the psalm must be long after the time of Solomon. In the quest for Davidic psalms we can never possibly rise above conjecture. Later ages regarded David as the father of sacred song, just as they regarded Moses as the author of Hebrew law.

There can be little doubt, however, that there are pre-exilic psalms or fragments in the Psalter. From Psalm cxxxvii. 3, 4 we may safely infer that already, by the time of the exile, there were songs of Jehovah or songs of Zion. We cannot tell what these songs were like; but when we remember that for nearly two centuries before the exile great prophets had been working—and we cannot suppose altogether ineffectually, for they had disciples—it is difficult to see why, granting the poetic power which the Hebrew had from the earliest times, pious spirits should not have expressed themselves in sacred song, or why some of these songs may not be in the Psalter.

We appear to be on tolerably sure ground in at least some of the "royal" psalms. Doubtless it is often very hard to say, as in Psalms ii., lxxii., whether the king is a historical figure or the Messianic King of popular yearning; and possibly (cf. lxxii.) a psalm which originally contemplated a historical king may have been in later times altered or amplified to fit the features of the ideal king. Other psalms, again (e.g., lxxxix., cxxxii.), clearly are the products of a time when the monarchy is no more. But there remain others, expressing, e.g. a wish for the king's welfare (xx., xxi.), which can only be naturally referred to a time when the king was on the throne. It is not absolutely impossible to refer these to the period of the Hasmoneans, who bore the title from the end of the second century B.C.; but the history of the canon renders this supposition extremely improbable. The contents of these psalms are not above pre-exilic possibility, and their position in the first book would, generally speaking, be in favour of the earlier date. Psalm xlv. also, which celebrates the marriage of a king to a foreign princess, seems almost to compel a pre-exilic date.

Some scholars, struck by the resemblance between many of the sorrowful psalms and the poetry of Jeremiah, have not hesitated to ascribe some of them to him (cf. xl. 2). Such a judgment is necessarily subjective, but there can be little doubt that Jeremiah powerfully influenced Hebrew religious poetry. The Greek superscriptions, again, which assign certain psalms to Haggai and Zechariah, though doubtless unreliable, are of interest in suggesting the liturgical importance of the period following the return from the exile. This period seems to have produced several psalms. Psalm cxxvi,, with its curiously complex feeling, apparently reflects the situation of that period, and the group of psalms which proclaim Jehovah as King, and ring with the notes of a "new song," were probably composed to celebrate the joy of the return and the resumption of public worship in the temple (xciii., xcv.-c., cf. xcvi. 1). The history of the next three centuries is very obscure, and many a psalm which we cannot locate may belong to that period; but the psalms which celebrate the law (i., xix. 7ff., cxix.) no doubt follow the reformation of Ezra in the fifth century.

It is not probable that there are many, if any, psalms later than 170-165 B.C. in the Maccabean period; some deny even this possibility, basing their denial on the history of the canon. But if the book of Daniel, which belongs to this same period, was admitted to the canon, there is no reason why the same honour should not have been conferred upon some of the psalms. The Maccabean period was fitted, almost more than any other in Israel's history, to rouse the religious passion of the people to song; and, as the possibility must be conceded, the question becomes one of exegesis. Exegetically considered, the claims of at least Psalms xliv., lxxiv., lxxix., lxxxiii. are indubitable. They speak of a desolation of the temple in spite of a punctilious fulfilment of the law, a religious persecution, a slaughter of the saints, a blasphemy of the holy name. No situation fits these circumstances so completely as the persecution of the Jews by Antiochus Epiphanes in 168 B.C., and these psalms betray many remarkable affinities with passages in the first book of the Maccabees. As long ago as the fifth century A.D. the sharp-sighted Theodore of Mopsuestia believed that there were seventeen Maccabean psalms; Calvin admitted at least three. It may be safely concluded, then, that the Psalter brings us within about a century and a half of the Christian era.

The criteria for determining the date of a psalm are few and meagre. The Psalter expresses the piety of more than half a millennium, and even the century cannot always be fixed. The language is often general, and the thoughts uttered would be as possible and appropriate to one century as another. Nearly forty years ago Nöldeke maintained that there were psalms of which we could not say with any definiteness to what period they belonged between 900 and 160 B.C. He himself referred Psalm ii. to Solomon, which had been referred by Hitzig to Alexander Jannaeus (105-78 B.C.). Even where the historical implications may seem fairly certain, there may be more than one legitimate interpretation. Psalm xlvi., e.g., which is usually regarded as a song of triumph sung after the departure of Sennacherib, is by some interpreted eschatologically; Zion is the ideal Zion of the latter days, and the stream that makes her glad is the stream of Paradise. Some psalms, of course, have their origin stamped very legibly upon them. Psalm cxxxvii. e.g., clearly implies that the exile is not long over. The presence of Aramaisms in a psalm is a fairly sure indication of a relatively late date. Within certain limits, also, its theological ideas may be a guide, though we know too little of the history of these ideas to use this criterion with much confidence. Still, so elaborate an emphasis on the omnipresence of God as we find in Psalm cxxxix. is only possible to a later age, and this inference is more than confirmed by its highly Aramaic flavour. Both these considerations render its ascription to David utterly untenable.