John Brown of Haddington's notes on Psalm 109
"Probably David penned this psalm with a view to Doeg or Ahithophel, and hence it is much like the 41st, 52nd, 55th, 124th, and 140th. But the Holy Ghost herein hath a mediate respect to Jesus, and to Judas the traitor, Acts 1:20. Observe, (1.) The psalmist's bitter complaints of his enemies, as spiteful, deceitful, false, restless, unjust, ungrateful, ver. 1-5. (2.) His fearful denunciations of divine vengeance against his distinguished foe; that he should be delivered into the hand of Satan; should have his prayers rejected, his life shortened, his substance wasted, and his posterity rendered miserable, ver. 6-20. (3.) His lamentation over his inward trouble, his approaching death, his instability of condition, pining sickness, reproach of enemies; and his prayers for mercy to himself, confusion to his enemies, and glory to his God, ver. 21-29. (4.) His triumph in God, as his supporter and deliverer amidst all his troubles, ver. 30-31.
While I sing, let me be affected with the sufferings of my Redeemer, and with the misery of these Jews and others, who abandon themselves to be his obstinate opposers. Let me implore, and by faith foresee the complete ruin of all my spiritual enemies; and the full redemption of my soul, and of the whole mystical body of Christ, notwithstanding all our sinful poverty and plagues. "
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