"Hear me speedily, O Lord." Hasten to hear me; do not delay. Literally, "Hasten; answer me." I am in imminent danger. Do not delay to come to my relief.
My spirit faileth - My strength is declining. I can hold out no longer. I am ready to give up and die.
Hide not thy face from me - Do not refuse or delay to look favorably upon me; to lift up the light of thy countenance upon me.
Lest I be like unto them that go down into the pit - Margin, "For I am become like." The idea is, Unless thou shalt lift up the light of thy countenance - unless thou shalt interpose and help me, I shall die. The "pit" here refers to the grave. See the notes at Psalm 28:1.

Hear me speedily - מהר maher, make haste to answer me. A few hours, and my state may be irretrievable. In a short time my unnatural son may put an end to my life.

Hear me speedily, O Lord: my spirit faileth,.... Ready to sink, swoon, and faint away, through the weight of the affliction on him, by reason of the persecution of his enemy, and for want of the divine Presence; hence the Targum renders it,
"my spirit desireth thee;''
see Song 5:6; and therefore entreats that God would hear and answer him quickly; or, "make haste to answer" him, and not delay, lest he should be quite gone. Wherefore it follows,
hide not thy face from me; nothing is more desirable to a good man than the "face" or presence of God, the light of his countenance, and sensible communion with him; which may be said to be "hid" when he withdraws his gracious presence, and withholds the discoveries of his love, and the manifestations of his free grace and favour; which he sometimes does on account of sin, and is the case at times of the best of saints; and is consistent with the love of God, though very grieving to them, and therefore here deprecated: the Targum is,
"cause not thy Shechinah to remove from me;''
lest I be like unto them that go down into the pit; either the house of the grave, as the Targum; look wan and pale, become lifeless and spiritless, or like a dead man; for as in the favour of God is life, his absence is as death: or the pit of hell, the pit of destruction; that is, be in such horror and despair, and under such apprehensions of divine wrath, as the damned feel.

David prays that God would be well pleased with him, and let him know that he was so. He pleads the wretchedness of his case, if God withdrew from him. But the night of distress and discouragement shall end in a morning of consolation and praise. He prays that he might be enlightened with the knowledge of God's will; and this is the first work of the Spirit. A good man does not ask the way in which is the most pleasant walking, but what is the right way. Not only show me what thy will is, but teach me how to do it. Those who have the Lord for their God, have his Spirit for their Guide; they are led by the Spirit. He prays that he might be enlivened to do God's will. But we should especially seek the destruction of our sins, our worst enemies, that we may be devotedly God's servants.

spirit faileth--is exhausted.

In this second half the Psalm seems still more like a reproduction of the thoughts of earlier Psalm. The prayer, "answer me speedily, hide not Thy face from me," sounds like Psalm 69:18; Psalm 27:9, cf. Psalm 102:3. The expression of languishing longing, כּלתה רוּחי, is like Psalm 84:3. And the apodosis, "else I should become like those who go down into the pit," agrees word for word with Psalm 28:1, cf. Psalm 88:5. In connection with the words, "cause me to hear Thy loving-kindness in the early morning," one is reminded of the similar prayer of Moses in Psalm 90:14, and with the confirmatory "for in Thee do I trust" of Psalm 25:2, and frequently. With the prayer that the night of affliction may have an end with the next morning's dawn, and that God's helping loving-kindness may make itself felt by him, is joined the prayer that God would be pleased to grant him to know the way that he has to go in order to escape the destruction into which they are anxious to ensnare him. This last prayer has its type in Exodus 33:13, and in the Psalter in Psalm 25:4 (cf. Psalm 142:4); and its confirmation: for to Thee have I lifted up my soul, viz., in a craving after salvation and in the confidence of faith, has its type in Psalm 25:1; Psalm 86:4. But the words אליך כסּיתי, which are added to the petition "deliver me from mine enemies" (Psalm 59:2; Psalm 31:16), are peculiar, and in their expression without example. The Syriac version leaves them untranslated. The lxx renders: ὅτι πρὸς σὲ κατέφυγον, by which the defective mode of writing כסתי is indirectly attested, instead of which the translators read נסתי (cf. נוּס על in Isaiah 10:3); for elsewhere not חסה but נוּס is reproduced with καταφυγεῖν. The Targum renders it מימרך מנּתי לפריק, Thy Logos do I account as (my) Redeemer (i.e., regard it as such), as if the Hebrew words were to be rendered: upon Thee do I reckon or count, כסּיתי = כּסתּי, Exodus 12:4. Luther closely follows the lxx: "to Thee have I fled for refuge." Jerome, however, inasmuch as he renders: ad te protectus sum, has pointed כסּיתי (כסּיתי). Hitzig (on the passage before us and Proverbs 7:20) reads כסתי from כּסא = סכא, to look ("towards Thee do I look"). But the Hebrew contains no trace of that verb; the full moon is called כסא (כסה), not as being "a sight or vision, species," but from its covered orb.
The כסּתי before us only admits of two interpretations: (1) Ad (apud) te texi = to Thee have I secretly confided it (Rashi, Aben-Ezra, Kimchi, Coccejus, J. H. Michaelis, J. D. Michalis, Rosenmller, Gesenius, and De Wette). But such a constructio praegnans, in connection with which כּסּה would veer round from the signification to veil (cf. כסה מן, Genesis 18:17) into its opposite, and the clause have the meaning of כּי אליך גּלּיתי, Jeremiah 11:20; Jeremiah 20:12, is hardly conceivable. (2) Ad (apud) te abscondidi, scil. me (Saadia, Calvin, Maurer, Ewald, and Hengstenberg), in favour of which we decide; for it is evident from Genesis 38:14; Deuteronomy 22:12, cf. Jonah 3:6, that כּסּה can express the act of covering as an act that is referred to the person himself who covers, and so can obtain a reflexive meaning. Therefore: towards Thee, with Thee have I made a hiding = hidden myself, which according to the sense is equivalent to חסיתּי, as Hupfeld (with a few MSS) wishes to read; but Abulwald has already remarked that the same goal is reached with כסּתי. Jahve, with whom he hides himself, is alone able to make known to him what is right and beneficial in the position in which he finds himself, in which he is exposed to temporal and spiritual dangers, and is able to teach him to carry out the recognised will of God ("the will of God, good and well-pleasing and perfect," Romans 12:2); and this it is for which he prays to Him in Psalm 143:10 (רצונך; another reading, רצונך). For Jahve is indeed his God, who cannot leave him, who is assailed and tempted without and within, in error; may His good Spirit then (רוּחך טובה for הטּובה, Nehemiah 9:20)
(Note: Properly, "Thy Spirit, רוּח הטּובה, a spirit, the good one, although such irregularities may also be a negligent usage of the language, like the Arabic msjd 'l-jâm‛, the chief mosque, which many grammarians regard as a construct relationship, others as an ellipsis (inasmuch as they supply Arab. 'l-mkân between the words); the former is confirmed from the Hebrew, vid., Ewald, 287, a.))
lead him in a level country, for, as it is said in Isaiah, Isaiah 26:7, in looking up to Jahve, "the path which the righteous man takes is smoothness; Thou makest the course of the righteous smooth." The geographical term ארץ מישׁור, Deuteronomy 4:43; Jeremiah 48:21, is here applied spiritually. Here, too, reminiscences of Psalm already read meet us everywhere: cf. on "to do Thy will," Psalm 40:9; on "for Thou art my God," Psalm 40:6, and frequently; on "Thy good Spirit," Psalm 51:14; on "a level country," and the whole petition, Psalm 27:11 (where the expression is "a level path"), together with Psalm 5:9; Psalm 25:4., Psalm 31:4. And the Psalm also further unrolls itself in such now well-known thoughts of the Psalm: For Thy Name's sake, Jahve (Psalm 25:11), quicken me again (Psalm 71:20, and frequently); by virtue of Thy righteousness be pleased to bring my soul out of distress (Ps 142:8; Psalm 25:17, and frequently); and by virtue of Thy loving-kindness cut off mine enemies (Psalm 54:7). As in Psalm 143:1 faithfulness and righteousness, here loving-kindness (mercy) and righteousness, are coupled together; and that so that mercy is not named beside towtsiy', nor righteousness beside תּצמית, but the reverse (vid., on Psalm 143:1). It is impossible that God should suffer him who has hidden himself in Him to die and perish, and should suffer his enemies on the other hand to triumph. Therefore the poet confirms the prayer for the cutting off (הצמית as in Psalm 94:23) of his enemies and the destruction (האביד, elsewhere אבּד) of the oppressors of his soul (elsewhere צררי) with the words: for I am Thy servant.