Guardrails Against Wrongful Use of the Imprecatory Psalms
Concerning the use of imprecatory Psalms prayers, Gurnall issued these warnings:
Do Not Pray Against Our Own Particular Enemies
Take heed thou dost not make thy private particular enemies the object of thy imprecation: we have no warrant, when any wrong us, to go and call fire from heaven upon them. We are bid indeed to ‘heap coals upon the enemy’s head,’ but they are of love, not of wrath and revenge. Job set a black brand upon this, and clears himself from the imputation of so great a sin,—‘If I rejoiced at the destruction of him that hated me, or lifted up myself when evil found him: neither have I suffered my mouth to sin, by wishing a curse to his soul,’ chap. 31:29, 30. He durst not wish his enemy ill, much less deliberately form a wish into a prayer, and desire God to curse him… Moses, I suppose, had as noble a spirit as any of these that style themselves men of honour, yet did he draw his sword upon Aaron, or curse Miriam, when they had used him so ill? I trow not, but bore all patiently; nay, when God declared his displeasure against Miriam for this affront put upon him, see how this holy man interceded for her with God, Numb. 12:13. This is valour of the right make, to overcome evil with good, and instead of seeking revenge on him that wrongs us, to have the mastery of our own corruption so far as to desire his good the more. Thus our Lord, when he was numbered amongst transgressors, even then interceded for the transgressors, Isa. 53:12; that is, those very men who used him so barbarously, while they were digging his heart out of his body with their instruments of cruelty, then was he begging the life of their souls with his fervent prayers.
Pray Against Plots, Not Persons
Secondly, when thou prayest against the enemies of God and his church, direct thy prayers rather against their plots than against their persons. Thus the apostles,—‘And now, Lord, behold their threatenings,’ Acts 4:29; not, ‘Confound their persons’, but, ‘Behold their threatenings,’ and so they leave their case with the Lord to set it right for them.
So David, 2 Sam. 15:31: ‘O Lord, I pray thee, turn the counsel of Ahithophel into foolishness.’ Indeed, God did do more, he destroyed plot and plotter also, and in this sense the saints may often say, with the prophet, ‘Thou hast done terrible things, we looked not for,’ and prayed not for, by pouring out his vengeance on the persons, when they have only prayed against their wicked designs.
Thirdly, When praying against the persons of those that are open enemies to God and his church, it is safest to pray indefinitely. ‘Let them all be confounded and turned back that hate Zion,’ Psa. 129:5; because we know not who of them are implacable, and who not, and therefore cannot pray peremptorily against particular persons. There may be an elect vessel for a time in open hostility against God and his church, whom afterwards God may consecrate to himself by converting grace, and so make him a holy vessel for the use of his sanctuary. We do, it is confessed, find some in Scripture prayed against by name,—Moses prayed against Korah and his accomplices, Numb. 16, and Paul against Alexander the coppersmith,—‘The Lord reward him according to his works;’ but these, and others in Scripture, had an extraordinary spirit, and are not to be patterns for us in this case.
Elias called fire from heaven upon the captains, but the disciples were soundly rebuked for a preposterous imitation of his act, who had not his spirit,—‘Ye know not what spirit ye are of.’ Pray thou for vengeance against all the implacable enemies of God, and leave him to direct thy arrow to its mark. Ahab was hit, though the arrow was shot at a venture. Prayers are sorted in heaven before their answer returns. Some of those emperors for whom the church in the primitive times prayed, yet proving implacable enemies to God and his people, felt the weight of those imprecations which, in general, they put up against the adversaries of the truth.
The Glory of God Should Be the Principle Aim
Fourthly, In praying against the implacable enemies of God and his church, the glory of God should be principally aimed at, and vengeance implored on them in order to advance that… The saddest consequence which attends the success of God’s enemies in the world is their pride and blasphemy against him, his truth, and church. Then they belch out their horrid blasphemies against Heaven, then they mock the poor saints, while they say unto them, ‘Where is now your God?’ But when God takes to himself power and strength, and confounds these, by bringing destruction upon their heads in ‘the midst of their wicked enterprises; when he recoils their own plots upon themselves, making them go off like a pistol in their pocket, to procure their own death and ruin; now the reproach is taken off, and they have an answer given home to their question, ‘Where is now your God?’ He is at their throat, with his sword of vengeance vindicating his glorious name upon them… This exaltation of the glorious name of God, every saint doth and should aim at in the prayers wherein he imprecates vengeance: ‘Let them be confounded and troubled for ever; yea, let them be put to shame, and perish; that men may know that thou, whose name alone is JEHOVAH, art the most high over the earth,’ Psa. 83:17.
Next time I'd like to wrap up with Gurnall's warning to a would-be Balaam. It's a bracing warning for sure.
 Frederic Henry Chase, Chrysostom: A Study in the History of Biblical Interpretation (Cambridge; London: Deighton Bell and Co.; George Bell and Sons, 1887), 49.
 Origen, however, interpreted this as a strict prophecy. It’s still not an adoption of the imprecation for use against his own personal enemies, but an interesting, if alternate, view nonetheless.
 Frederic Henry Chase, Chrysostom: A Study in the History of Biblical Interpretation (Cambridge; London: Deighton Bell and Co.; George Bell and Sons, 1887), 54–55.
 William Gurnall and John Campbell, The Christian in Complete Armour (London: Thomas Tegg, 1845), 728.