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Fausset's Bible Dictionary [1]

Title of Psalm 9. Labben is an anagram for Nabal ("the fool" or wicked); "concerning the dying ( Muth ) of the fool," as  Psalms 9:12;  Psalms 9:16-17, "Thou hast destroyed the wicked, Thou hast put out their name forever and ever." "The wicked is snared in the work of his own hands." Higgaion ("meditation"); Selah ("pause".) "The wicked shall be turned into hell," etc. Saul slain by the Philistines by whom he had sought to slay David, and receiving the last thrust from one of the Amalekites whom he ought to have destroyed, and Nabal ("fool") dying after his selfish surfeit when churlishly he had refused aught to David's men who had guarded him and his, are instances of the death of such world-wise "fools" ( 1 Samuel 25:26;  1 Samuel 25:38;  2 Samuel 3:33;  Psalms 14:1). (See Nabal .) The Septuagint and Vulgate versions read concerning the mysteries of the Son," namely, the divine Son's death, the earnest of His final victory over the last "enemy" ( Psalms 9:6).

Smith's Bible Dictionary [2]

Muth-labben. "To the chief musician upon Muth-labben" is the title of  Psalms 9:1, which has given rise to infinite conjecture. It may be either upon the Death , ( muth ), of the Fool , ( labben ), as an anagram on Nabal, or as Gesenius, "to be chanted by boys, with virgins' voices," that is, in the soprano.

Easton's Bible Dictionary [3]

 Psalm 9 2 Samuel 18:33

Hastings' Dictionary of the Bible [4]

Muth-Labben . See Psalms, p. 772 a .

Holman Bible Dictionary [5]

 Psalm 9:1

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [6]

(Hebrew, fully, al muth labben', עִלאּמוּת לִבֵּן , Upon- the Death To The Son; Sept. Ὑπὲρ Τῶν Κρυφίων Τοῦ Νἱοῦ ; Vulg. Pro Occultis Filii; Auth. Ver. " upon Muth-labben"), a phrase occurring only in the title of Psalms 9. The following are conjectures that have been made regarding its import:

1.' Perhaps the favorite opinion of modern critics, of Gesenius and De Wette among the rest, is to connect the Hebrew words so as to read 'almuth labben, "with the voice of virgins [to be sung] by boys." But, granting the lawfulness of this critical effort, there is considerable difficulty in extracting the translation desiderated. The word 'alamoth does occur in probably some such meaning (Psalms 46, title;  1 Chronicles 15:20); and it has been preferred by critics who modify the opinion now under consideration, to the extent of arriving at this word by altering the vowel- points as well as the division of the words. (See Alamoth).

Yet, after doing so, they have to face an awkward difficulty, arising from the absence of the preposition 'al, "upon;" since they require this little word to become the first syllable of their noun. It is evident that the Sept. and Vulgate must have read עִל עֲלֻמוֹת , "concerning the mysteries," and so the Arabic and Ethiopic versions. The Targum, Symmachus ( Περὶ Θανάτου Τοῦ Υἱοῦ ), and Jerome (Super Morte Filii), in his translation of the Hebrew, adhered to the received text, while Aquila ( Νεανιότητος Τοῦ Υἱοῦ ), retaining the consonants as they at present stand, read Al-Muth as one word, עִלְמוּת , "youth," which would be the regular form of the abstract noun, though it does not occur in Biblical Hebrew. In support of the reading עלמות as one word, we have the authority of twenty-eight of Kennicott's MSS., and the assertion of Jarchi that he had seen it so written, as in  Psalms 48:14, in the Great Masorah. If the reading of the Vulgate and Sept. be correct with regard to the consonants, the words might be pointed thus, עִל עֲלָמוֹת , Al 'Alamoth, " upon Alamoth," as in the title of Psalms 46; and לבן is possibly a fragment of לַבְנֵי קֹרִח , Libney Korach, "for the sons of Korah," which appears in the same title.

2. It has been very common to suppose that there is here the name of a person. The Jewish commentator Kimchi, according to Gesenius, mentions that some explained it, "upon the death of Labben," a person wholly unknown. But commonly the first syllable of Labben has been taken to be the ordinary Hebrew prefix preposition, "to, for, concerning." The Targum renders the title of the psalm, "On the death of the man who came forth from between ( בֵּין ) the camps," alluding to Goliath, the Philistine champion ( אַישׁ הִבֵּינִיַם ,  1 Samuel 17:4). That David composed the psalm as a triumphal song upon the slaughter of his gigantic adversary was a tradition which is mentioned by Kimchi merely as an On Dit. An old opinion, maintained at present by Furst, is that it should be translated "upon the death of Ben," who is named among the Levites appointed to preside over the music at the removal of the ark to its resting-place ( 1 Chronicles 15:18), while he is not named in the narrative of the actual removal; indeed, his place seems to be filled by another Azaziah ( 1 Chronicles 15:20-21); and we are reminded of the sudden death of Uzzah, when the removal was attempted on an earlier occasion Hengstenberg. however, has revived an old opinion of Grotius originally mentioned, but not adopted, by Jarchi that Labben is transposed for Nabal, yet not so much with reference to the individual man as with reference to " the fool," which is emphatically noticed as the meaning of his name; and he thinks the psalm refers a good deal to the end of the wicked. Donesh supposes that Labben was the name of the man who warred with David in those days, and to whom reference is made as "the wicked" in  1 Chronicles 15:5. Arama (quoted by Dr. Gill in his Exposition) identifies him with Saul. Jarchi says that some regarded Labben as the name of a foreign prince who made war upon the Israelites, and upon whose overthrow this song of praise was composed.

3. The word Ben being the common Hebrew word for "son," and so translated in this title by the ancient versions generally, the translation has been offered, "upon the death of the son," or "upon dying in reference to the son," viz. David's son Absalom, for whom it is recorded that he wept and mourned passionately ( 2 Samuel 18:33). The renderings of the Sept. and Vulgate induced the early Christian commentators to refer the psalm to the Messiah. Augustine understands "the son" as "the only- begotten Son of God." The Syriac version is quoted in support of this interpretation, but the titles of the Psalms in that version are generally constructed without any reference to the Hebrew, and therefore it cannot be appealed to as an authority.

4. As in the case of other titles of the Psalms, this has been taken to be a musical instrument, or more commonly and probably the name of an air to which the psalm was sung. This title might then be translated, "upon dying [which has happened] to the son," or "upon 'Die for the son."' So Hupfeld, that it was the commencement of an old song, signifying "death to the son." Delitzsch adopts this sort of explanation, but translates differently, "upon 'Death makes white.' Hitzig and others regard it as an abbreviation containing a reference to  Psalms 48:14. According to Jarchi, "this song is of the distant future when the childhood and youth of Israel shall be made white ( יתלבן ), and their righteousness be revealed and their salvation draw nigh, when Esau and his seed shall be blotted out." He takes עִלְמוּת as one word, signifying "youth," and לִבֵּן = לְלִבֵּן , "to whiten." Menahem, a commentator quoted by Jarchi, interprets the title as addressed "to the musician upon the stringed instruments called Alamoth, to instruct," taking לִבֵּן as if it were לְהָבַין or לְבוֹנֵן . The difficulty of the question is sufficiently indicated by the explanation which Gesenius hinself (Thes. page 741 a) was driven to adopt, that the title of the psalm signified that it was "to be chanted by boys with virgins' voices," i.e., in the soprano. (Comp. the briefer form, "unto death,"  Psalms 48:9). (See Psalms).

International Standard Bible Encyclopedia [7]

muth - lab´en ( לבּן מוּת , mūth labbēn , "death of Ben," or "of the son";   Psalm 9 , title). See Psalms .