Jordan - Psalm 18

A song my siblings and I used to sing went like this:

I will call upon the Lord 

Who is worthy to be praised

So shall I be safe from my enemy

I will call upon the Lord

The Lord liveth!

And blessed be the rock!

And may the God of our salvation be exalted.

I had no idea that came from Psalm 18 (and, I guess Samuel 22 is similar)!  This psalm is so interesting.  From verses that bring me back to childhood to verses that make me cringe and want to rebuke the psalmist.  The psalm is in a few parts (from what i can tell):
1-6: Opening/intro
7-15: Power of God
16-24: God favors the psalmist and delivers him from enemies
25-36: God's power and favor gives the psalmist perceived power
37-45: Psalmist abuses power to beat the living crap out of people
46-50: Psalmist loves God and thanks God

One of these parts is not like the others, can you tell?  In verses 41-42 there are sentences like "They cried for help, but there was no one to save them...I beat them fine, like dust before the wind."  I mean, seriously??  Its one thing that God gives us protection and power to defend ourselves, but does God really give us the power to smash our enemies and pursue them even as they flee and cry out for help?

Just reading those verses spoils the rest of it for me.  People who combine the love of God with the ability to have power and conduct violence have no idea what love is.