Biblical Commentary on the Old Testament, by Carl Friedrich Keil and Franz Delitzsh, [1857-78], at sacred-texts.com
Talismanic Song in Time of War and Pestilence
The primeval song is followed by an anonymous song (inscribed by the lxx without any warrant τῷ Δαυίδ), the time of whose composition cannot be determined; and it is only placed in this order because the last verse accords with the last verse but one of Ps 90. There the revelation of Jahve's work is prayed for, and here Jahve promises: I will grant him to see My salvation; the "work of Jahve" is His realized "salvation." The two Psalms also have other points of contact, e.g., in the מעון referred to God (vid., Symbolae, p. 60).
In this Psalm, the Invocavit Psalm of the church, which praises the protecting and rescuing grace which he who believingly takes refuge in God experiences in all times of danger and distress,
(Note: Hence in J. Shabbath 8, col. 2, and Midrash Shocher tob on Psa 91:1 and elsewhere, it is called, together with Psa 3:1-8, (פגעים) שיר פגועין, a song of occurrences, i.e., a protective (or talismanic) song in times of dangers that may befall one, just as Sebald Heyden's Psalm-song, "He who is in the protection of the Most High and resigns himself to God," is inscribed "Preservative against the pestilence.")
the relation of Psa 91:2 to Psa 91:1 meets us at the very beginning as a perplexing riddle. If we take Psa 91:1 as a clause complete in itself, then it is tautological. If we take אמר in Psa 91:2 as a participle (Jerome, dicens) instead of אמר, ending with Pathach because a construct from (cf. Psa 94:9; Psa 136:6), then the participial subject would have a participial predicate: "He who sitteth is saying," which is inelegant and also improbable, since אמר in other instances is always the 1st pers. fut. If we take אמר as 1st pers. fut. and Psa 91:1 as an apposition of the subject expressed in advance: as such an one who sitteth.... I say, then we stumble against יתלונן; this transition of the participle to the finite verb, especially without the copula (וּבצל), is confusing. If, however, we go on and read further into the Psalm, we find that the same difficulty as to the change of person recurs several times later on, just as in the opening. Olshausen, Hupfeld, and Hitzig get rid of this difficulty by all sorts of conjectures. But a reason for this abrupt change of the person is that dramatic arrangement recognised even in the Targum, although awkwardly indicated, which, however, as first of all clearly discerned by J. D. Michaelis and Maurer. There are, to wit, two voices that speak (as in Psa 121:1-8), and at last the voice of Jahve comes in as a third. His closing utterance, rich in promise, forms, perhaps not unaccidentally, a seven-line strophe. Whether the Psalm came also to be executed in liturgical use thus with several voices, perhaps by three choirs, we cannot tell; but the poet certainly laid it out dramatically, as the translation represents it. In spite of the many echoes of earlier models, it is one of the freshest and most beautiful Psalms, resembling the second part of Isaiah in its light-winged, richly coloured, and transparent diction.
As the concealing One, God is called עליון, the inaccessibly high One; and as the shadowing One שׁדּי, the invincibly almighty One. Faith, however, calls Him by His covenant name (Heilsname) יהוה and, with the suffix of appropriation, אלהי (my God). In connection with Psa 91:1 we are reminded of the expressions of the Book of Job, Job 39:28, concerning the eagle's building its nest in its eyrie. According to the accentuation, Psa 91:2 ought to be rendered with Geier, "Dicit: in Domino meo (or Domini) latibulum, etc." But the combination אמר לה is more natural, since the language of address follows in both halves of the verse.
יקושׁ, as in Pro 6:5; Jer 5:26, is the dullest toned from for יקושׁ or יוקשׁ, Psa 124:7. What is meant is death, or "he who has the power of death," Heb 2:14, cf. Ti2 2:26. "The snare of the fowler" is a figure for the peril of one's life, Ecc 9:12. In connection with Psa 91:4 we have to call to mind Deu 32:11 : God protects His own as an eagle with its large strong wing. אברה is nom. unitatis, a pinion, to אבר, Isa 40:31; and the Hiph. הסך, from סכך, with the dative of the object, like the Kal in Psa 140:8, signifies to afford covering, protection. The ἅπαξ λεγ. סחרה, according to its stem-word, is that which encompasses anything round about, and here beside צנּה, a weapon of defence surrounding the body on all sides; therefore not corresponding to the Syriac sḥārtā', a stronghold (סהר, מסגּרת), but to Syriac sabrā', a shield. The Targum translates צנּה with תּריסא, θυρεός, and סחרה with עגילא, which points to the round parma. אמתּו is the truth of the divine promises. This is an impregnable defence (a) in war-times, Psa 91:5, against nightly surprises, and in the battle by day; (b) in times of pestilence, Psa 91:6, when the destroying angel, who passes through and destroys the people (Exo 11:4), can do no harm to him who has taken refuge in God, either in the midnight or the noontide hours. The future יהלך is a more rhythmical and, in the signification to rage (as of disease) and to vanish away, a more usual form instead of ילך. The lxx, Aquila, and Symmachus erroneously associate the demon name שׁד with ישׁוּד. It is a metaplastic (as if formed from שׁוּד morf de) future for ישׁד, cf. Pro 29:6, ירוּן, and Isa 42:4, ירוּץ, frangetur. Psa 91:7 a hypothetical protasis: si cadant; the preterite would signify cediderint, Ew. 357, b. With רק that which will solely and exclusively take place is introduced. Burk correctly renders: nullam cum peste rem habebis, nisi ut videas. Only a spectator shalt thou be, and that with thine own eyes, being they self inaccessible and left to survive, conscious that thou thyself art a living one in contrast with those who are dying. And thou shalt behold, like Israel on the night of the Passover, the just retribution to which the evil-doers fall a prey. שׁלּמה, recompense, retribution, is a hapaxlegomenon, cf. שׁלּמים, Isa 34:8. Ascribing the glory to God, the second voice confirms or ratifies these promises.
The first voice continues this ratification, and goes on weaving these promises still further: thou hast made the Most High thy dwelling-place (מעון); there shall not touch thee.... The promises rise ever higher and higher and sound more glorious. The Pual אנּה, prop. to be turned towards, is equivalent to "to befall one," as in Pro 12:21; Aquila well renders: ου ̓ μεταχθήσεται πρὸς σὲ κακία. לא־יקרב reminds one of Isa 54:14, where אל follows; here it is בּ, as in Jdg 19:13. The angel guardianship which is apportioned to him who trusts in God appears in Psa 91:11, Psa 91:12 as a universal fact, not as a solitary fact and occurring only in extraordinary instances. Haec est vera miraculorum ratio, observes Brentius on this passage, quod semel aut iterum manifeste revelent ea quae Deus semper abscondite operatur. In ישּׂאוּנך the suffix has been combined with the full form of the future. The lxx correctly renders Psa 91:12: μήποτε προσκόψῃς πρὸς λίθον τὸν πόδα σου, for נגף everywhere else, and therefore surely here too and in Pro 3:23, has a transitive signification, not an intransitive (Aquila, Jerome, Symmachus), cf. Jer 13:16. Psa 91:13 tells what he who trusts in God has power to do by virtue of this divine succour through the medium of angels. The promise calls to mind Mar 16:18, ὄφεις ἀροῦσι, they shall take up serpents, but still more Luk 10:19 : Behold, I give you power to tread ἐπάνω ὄφεων καὶ σκορπίων καὶ ἐπὶ πᾶσαν τὴν δύναμιν τοῦ ἐχθροῦ. They are all kinds of destructive powers belonging to nature, and particularly to the spirit-world, that are meant. They are called lions and fierce lions from the side of their open power, which threatens destruction, and adders and dragons from the side of their venomous secret malice. In Psa 91:13 it is promised that the man who trusts in God shall walk on over these monsters, these malignant foes, proud in God and unharmed; in Psa 91:13, that he shall tread them to the ground (cf. Rom 16:20). That which the divine voice of promise now says at the close of the Psalm is, so far as the form is concerned, an echo taken from Ps 50. Psa 50:15, Psa 50:23 of that Psalm sound almost word for word the same. Gen 46:4, and more especially Isa 63:9, are to be compared on Psa 50:15. In B. Taanith 16a it is inferred from this passage that God compassionates the suffering ones whom He is compelled by reason of His holiness to chasten and prove. The "salvation of Jahve," as in Psa 50:23, is the full reality of the divine purpose (or counsel) of mercy. To live to see the final glory was the rapturous thought of the Old Testament hope, and in the apostolic age, of the New Testament hope also.