Albert Barnes' Bible Commentary
Psalms 145 - Introduction
This is also a Psalm of David, and the last of the series in this part of the collection. It is entitled simply, “Of Praise,” or, in the Hebrew, “Praise by David,” or “Praise of David;” that is, one of David’s songs of praise. It is an “alphabetical” psalm; that is, each verse begins with a letter of the Hebrew alphabet. The arrangement in this respect is complete, except that the Hebrew letter nun (נ n, “n”) is omitted, for which no reason can be assigned, unless it was from a desire that the psalm might consist of three equal parts of seven verses each. In the Septuagint, Syriac, Arabic, Latin Vulgate, and Aethiopic versions, this omission is attempted to be supplied by inserting between Psalms 145:13 a verse which in Hebrew would begin with the Hebrew letter nun (נ n, “n”), - נאמן, etc.: - “Faithful is the Lord in all his words, and holy in all his works.” This is taken from Psalms 145:17 of the psalm by the change of a word in the beginning - “faithful” for “righteous,” נאמן for צדיק. There is no authority for this, however, in the MSS., and it is evidently an attempt to supply what seemed to be an omission or defect in the composition of the psalm. The verse is not in the Chaldee Paraphrase, or in the version of Aquila and Theodotion; and it is certain that as early as the time of Origen and Jerome it was not in the Hebrew text. The Masorites and the Jewish commentators reject it. The sense is in no way affected by the insertion or omission of this, since the verses of the psalm have no necessary connection in meaning - the composition, as in most of the alphabetical psalms, being made up of independent sentiments suggested in part at least by the necessity of commencing each verse with a particular letter.
The psalm does not admit of any particular analysis, and it is impossible now to ascertain the occasion on which it was written.