In today’s (chronological) Bible reading… Psalms 108, 109… we see 2 psalms of David that seem to speak from each end of the spectrum.
Psalm 108 is a song of a warrior. In it, David, the warrior, looking battle in the eye, says, “I will praise!” (v.1-6), “I will listen!” (v.7-9), and “I will conquer!” (v.10-12).
Psalm 109 is an “imprecatory psalm”; one of several in the book of Psalms. Imprecatory psalms call for God’s judgment on enemies, and for God’s justice to be done. These psalms are hard for us to understand today, in light of our “cultured sensibilities”. But, we must remember, they are songs asking for God to act in accordance to His holiness and righteousness, asking Him to act on behalf of the person to whom He has made powerful promises.
If these acts are within God’s will and according to His plan, they will be done. if not, they will not. I would suppose it would be a rare occasion – a very rare occasion – that would justify such a prayer for God’s harsh justice. It is to be a common occurrence – a very common occurrence – that Christians show love… even in times when vengeance might be justified.