They shall curse. Interpreters are divided in their opinions about the meaning of these words. One class would render them as expressive of a desire or wish: Let them curse, provided that thou bless: let them arise, and be clothed with confusion Another class, and with them I readily agree, adopt the future tense of the indicative mood, They shall curse, etc. Should any prefer to understand the passage as indicating, on the part of the Psalmist, his resolution to suffer and submit to the curses of his enemies, I do not oppose their interpretation. In my opinion, however, those who view the words as a prayer, misinterpret them; because David, having already presented his petitions to God, and being secure in his favor, seems now rather to boast that their cursing will do him no harm; for Thou, says he, wilt bless me. By this means, he proves how little and how lightly he regarded the menaces of his enemies, though they might assail him by the poison of the tongue, and the power of the sword. From the example of David, let us learn to form the resolution of engaging God on our side, who can baffle all the designs of our enemies, and inspire us with courage to set at defiance their malice, wickedness, audacity, power, and fury. And then, indeed, it is that the loving-kindness of God appears, when it banishes from our minds the fears which we entertain of the threatenings of the world. Therefore, relying upon the grace of God, boldly setting at nought the machinations and attacks of his enemies, believing that they could not prevail against God's blessing, David raises the shout of triumph even in the midst of the battle. This truth is still more impressively inculcated in the succeeding clause of the verse: Though they arise, yet shall they be put to shame. By these words it is obviously his design to intimate that the ungovernable violence of his enemies is not yet subdued, but that he can endure all their fury and foam so long as the hand of God is stretched forth to maintain and defend him; and thus he animates and fortifies himself against all the pride of the world, and, at the same time, by his example emboldens all the faithful, so that they do not feel dejected even when the perverseness of their enemies seems to get the advantage over them, and to menace them with instant destruction. Cherishing such a hope, he trusts that, for the future, he shall be delivered from all his sorrows. Whence let us learn to bear patiently and meekly our trials, until the fit season and the full time, which God hath appointed, arrive for turning our weeping into joy. In the following verse he proceeds in the same strain of exultation, because, though he beholds the ungodly assuming a lofty air, yet, looking beyond the present state of things with the eye of faith, he entertains no doubt that God will frustrate all their designs, and pour contempt upon all their schemes.

Let them curse, but bless thou - See Psalm 109:17. Let them continue to curse me, provided thou wilt bless me. I am willing to bear all these reproaches, if I may have thy favor. That favor I value infinitely more than I do theirs; and it is a small matter that I am reviled and cursed by people, if I may secure the favor and friendship of God.
When they arise - When they rise up against me; when they attempt to persecute me.
Let them be ashamed - Let them be disappointed; let them not be successful in their designs against me. On the word "ashamed," see Job 6:20, note; Psalm 25:2-3, note.

Let them curse, but bless thou - See on Psalm 109:20 (note): Of the mode of interpretation recommended there, this verse gives additional proof.

Let them (p) curse, but bless thou: when they arise, let them be ashamed; but let thy servant rejoice.
(p) They will gain nothing by cursing me.

Let them curse, but bless thou,.... Let them curse me, as Shimei did David, the type of Christ; let them curse themselves, as they did; or my people: or "let them be cursed", as the Syriac version; cursed in life and at death, and to all eternity: but "bless thou me", the Messiah; as he did, when he raised him front the dead, set him at his right hand, and gave him a name above everyone, and made him most blessed for evermore; and bless my people with all spiritual blessings of grace, and with eternal glory and happiness. Or "be thou blessed"; let honour, blessing, and praise, be continually ascribed to thee; if God does but bless, it is no matter if wicked men curse, so Aben Ezra and Kimchi interpret it; see 2-Samuel 16:11.
When they arise, let them be ashamed; be suffered to do those things which may bring shame and disgrace upon them; or let them be disappointed and so confounded, as the Jews were; who though they so far gained their point as to bring Christ to the dust of death and the grave, yet to their great confusion he arose again from the dead; or let them be ashamed at the last day, as they will be when Christ shall come in the clouds of heaven and be their Judge, who will then be glad to shelter themselves in rocks and caves. This is imprecated to be done
when they shall arise: rise up against Christ to take away his life; rise up against his disciples to persecute them, against his Gospel to contradict and blaspheme it, and against his cause and interest to crush it; or against the Romans, to shake off their yoke, when they were brought to great shame and confusion; or when they shall arise at the resurrection of the dead, which will be to shame and everlasting contempt, Daniel 12:2.
But let thy servant rejoice; the Messiah, who appeared in the form of a servant; came not as a temporal lord and prince, to be ministered unto, but as a servant, to minister to others; and who is a servant of God's choosing, calling, and sending, and whom he faithfully served; and who, as prayed for, did rejoice in the strength of the Lord, given him as man; and in the salvation wrought for and by him, Psalm 21:1, in the work of the Lord prospering in his hand; in his victory over sin, Satan, the world, and death; in the presence of God he was made glad with, and in the glory promised him, which he had with his Father before the world was, Psalm 16:11.

In confidence that God's blessing would come on him, and confusion and shame on his enemies (Psalm 73:13), he ceases to regard their curses, and anticipates a season of joyful and public thanksgiving; for God is near to protect (Psalm 16:8; Psalm 34:6) the poor from all unrighteous judges who may condemn him.