Psalms 42:5

“If I forget thee, O Jerusalem, etc.] This was said by one or everyone of the Levites; or singers, as Aben Ezra and Kimchi; or by the congregation of Israel, as Jarchi; by one of them, in the name of the rest; or by the composer of the psalm. The Targum is, “the voice of the Spirit of God answered and said, “if I forget”, etc.” that is, to weep over the calamities of Jerusalem; which might be thought, if the songs of Zion were sung; or to pray for the restoration of her prosperity and peace; as the church of Christ may be said to be forgotten, when men forget to mourn over its breaches, and show no concern for the reparation of them; or at the death of principal persons, which they lay not to…”

“Hence he chides his despondent soul, assuring himself of a time of joy. help of his countenance--or, "face" (compare Num 6:25; Psa 4:6; Psa 16:11).”

“Why art thou cast down, O my soul? - Margin, bowed down. The Hebrew word means to bow down, to incline oneself; then, usually, to prostrate oneself as in public worship; and then, to sink down under the weight of sorrow; to be depressed and sad. The Septuagint renders it, “Why art thou grieved?” - περίλυπος perilupos. So the Vulgate. This is an earnest remonstrance addressed by himself to his own soul, as if there were really no occasion for this excessive depression; as if he cherished his grief improperly. There was a brighter side, and he ought to turn to that, and take a more cheerful view of the matter. He had allowed his mind to rest on the dark side, to look at the discouraging…”

“For - Heb. for the salvations of his face, for those supports, deliverances and comforts which I doubt not I shall enjoy both in his presence and sanctuary, and from his presence, and the light of his countenance. Psalms 42:6”

“42:5-6 The psalmist encourages himself with questions and answers. 42:5 The psalmist feels depressed, but it does not incapacitate him. He remembers that the living God is his Savior. This verse is repeated in 42:11 and 43:5.”

“Why art thou cast down: Heb. Why art thou bowed down, Psa 42:11, Psa 35:14, Psa 43:5, Psa 55:4, Psa 55:5, Psa 61:2, Psa 142:2, Psa 142:3, Psa 143:3, Psa 143:4; Sa1 30:6; Mar 14:33, Mar 14:34 hope: Psa 27:13, Psa 27:14, Psa 37:7, Psa 56:3, Psa 56:11, Psa 71:14; Job 13:15; Isa 50:10; Lam 3:24-26; Rom 4:18-20; Heb 10:36, Heb 10:37 praise him: or, give thanks for the help: etc. or, his presence is salvation, Psa 44:3, Psa 91:15, Psa 91:16; Num 6:26; Mat 1:23, Mat 28:20 Psalms 42:6”