Explaining the Imprecatory Psalms to a Child

How would you explain the imprecatory psalms to a child? Here is F. G. Hibbard's account:

I happened to be reading one of the one imprecatory psalms [in family worship], and as I paused to remark, my little boy, a lad of ten years, asked with some earnestness: "Father, do you think it right for a good man to pray for the destruction of his enemies like that?" and at the same time referred me to Christ as praying for his enemies. I paused a moment to know how to shape the reply so as to fully meet and satisfy his enquiry, and then said, "My son, if an assassin should enter the house by night, and murder your mother, and then escape, and the sheriff and citizens were all out in pursuit, trying to catch him, would you not pray to God that they might succeed and arrest him, and that he might be brought to justice?" "Oh yes!" said he, "but I never saw it so before. I did not know that that was the meaning of these Psalms." "Yes," said I, "my son, the men against whom David prayers were bloody men, men of falsehood and crime, enemies to the peace of society, seeking his own life, and unless they were arrested and their wicked devices defeated, many innocent persons must suffer." The explanation perfectly satisfied his mind.

F. G. Hibbard, The Psalms Chronologically Arranged, with Historical Introductions; and a General Introduction to the Whole Book, 5th ed. (New York: Carlton & Porter, 1856), 120. Cited in John N. Day, Crying for Justice: What the Psalms Teach Us About Mercy and Vengeance in an Age of Terrorism.