Vengeance is whose?

"The Psalms urge us to “seek peace, and pursue it” (34:14), an exhortation written by one who is teaching his family the fear of the Lord. The Psalms promise that “there is posterity for the peaceable” (37:37, NRSV; “there is a future for the man of peace,” NIV). Someone may retort that the imprecatory psalms strike a different note; the point is conceded: human emotions run high when people are provoked. But, strikingly, the imprecatory psalms call on God to take punitive action in accord with his promise/principle, “Vengeance is mine; I will repay”—a major plank in the shalom position (Deut 32:35). The Writings segment of the canon advocates a strategy of desisting from personal vengeance when provoked.”— Martens, War in the Bible and Terrorism in the Twenty-First Century, pp. 36-37