The spiritual dimensions of the psalms will often encompass fighting and battles. This seems paradoxical because many people believe that spiritual matters are all full of love and peace.
But Christians believe that they are in a continual war, that we are fighting sin in ourselves, temptations, the status quo, demonic principalities, spiritual sloth, despair, faithlessness, and countless other evils. They believe that Jesus not only came to save humans from death but that He came to plant God's kingdom in a rebellious world.
By managing to live a perfect life -- the only human to ever do so-Jesus did something mythic. He won back the authority man lost against sin, sickness, death, and demonic entities. Just as the first Adam caused us to be born subject to those things, Jesus -- the second Adam-- restored us again and destroyed/spoiled demonic princes.
One can believe all this if one has heart that loves myth. The world itself is a mythic place where words have power and spirit - kotodamai. Christians believe that doctrine is no mere set of rule to be believed but an explanation of how the world works, and a system which describes how to use God's power over demonic princes and earthly evils.
When the psalmist says, "For the enemy hath persecuted my soul; he hath smitten my life down to the ground; he hath made me to dwell in darkness, as those that have been long dead," he's not only thinking of human enemies. He's thinking of the relentlessness of the demonic, the relentlessness of sickness, the relentless choreography of evil that pursues those who love God. I say "choreography of evil" because evil is often directed, planned, and orchestrated.
Most people suffer in some ways because humans live in a fallen world. But there's a kind of suffering that pursues people - especially good people- because of the word of God is within them.
It's a harsh relentless suffering that can only be fought and endured and won with God's help...because it's a suffering whose sole end is to make the believer turn from God.
This is why the psalmist asks God for help. The psalmist is aware that God has power against evil and refuses to turn his eyes from God's truth.
1Hear my prayer, O LORD, give ear to my supplications: in thy faithfulness answer me, and in thy righteousness.
2And enter not into judgment with thy servant: for in thy sight shall no man living be justified.
3For the enemy hath persecuted my soul; he hath smitten my life down to the ground; he hath made me to dwell in darkness, as those that have been long dead.
4Therefore is my spirit overwhelmed within me; my heart within me is desolate.
5I remember the days of old; I meditate on all thy works; I muse on the work of thy hands.
6I stretch forth my hands unto thee: my soul thirsteth after thee, as a thirsty land. Selah.
7Hear me speedily, O LORD: my spirit faileth: hide not thy face from me, lest I be like unto them that go down into the pit.
8Cause me to hear thy lovingkindness in the morning; for in thee do I trust: cause me to know the way wherein I should walk; for I lift up my soul unto thee.
9Deliver me, O LORD, from mine enemies: I flee unto thee to hide me.
10Teach me to do thy will; for thou art my God: thy spirit is good; lead me into the land of uprightness.
11Quicken me, O LORD, for thy name's sake: for thy righteousness' sake bring my soul out of trouble.
12And of thy mercy cut off mine enemies, and destroy all them that afflict my soul: for I am thy servant.