Charles Ellicott Commentary Psalms 109:28-31

"Let them curse, but bless thou: When they arise, they shall be put to shame, But thy servant shall rejoice. Let mine adversaries be clothed with dishonor, And let them cover themselves with their own shame as with a robe. I will give great thanks unto Jehovah with my mouth; Yea, I will praise him among the multitude. For he will stand at the right hand of the needy, To save him from them that judge his soul." — Psalms 109:28-31 (ASV)

It is impossible not to notice the anti-climax in these verses, if they are spoken by the same person as Psalms 109:16-20, and directed against the same enemies, of whom the one there singled out is the prominent figure. It is not only that the effect is weakened by the change back to the plural number, but the same imprecations are repeated in a diluted and modified form. But perhaps in Psalms 109:28 we should drop the optative, and read, “they will curse, but you bless.”