Who is the Enemy?

Psalms 143
3 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.

A Thought
As beautiful as many of the passagas in Psalms are, there are just too many references to enemies for me to spiritually or rationally comprehend. So, this post provides (maybe a little too much) background for my continued consideration on this subject.

Webster 1828
EN'EMY, n. [L. inimicus.]
1. A foe; an adversary. A private enemy is one who hates another and wishes him injury, or attempts to do him injury to gratify his own malice or ill will. A public enemy or foe, is one who belongs to a nation or party, at war with another.
I say to you, love your enemies. Matt.5.
Enemies in war; in peace friends.
2. One who hates or dislikes; as an enemy to truth or falsehood.
3. In theology, and by way of eminence, the enemy is the Devil; the archfiend.
4. In military affairs, the opposing army or naval force in war, is called the enemy.

Psalm 64 With John Gill Commentary In Italics1
Hear my voice, O God, in my prayer: preserve my life from fear of the enemy.....David had his enemies. Saul and his courtiers, and was afraid of them; Christ had his enemies the wicked Jews, who sought his life before the time, and therefore he walked no more in Judea till near the time; and whose human nature was sometimes possessed of the fears of death, though they were sinless ones: the church and people of God have their enemies; as the men of the world, who revile, reproach, and persecute them; Satan their adversary, who goes about seeking to devour them.

Scattered Thoughts
Sorry, I just don't have enemies. I almost feel I should apologize. I think it's a genetic predisposition.

The essense of a normal life, Christian or non-Christian, may be a grand war against one's enemies, with God on one's side. Hense, references to enemies in the Psalms.

Me, I'm a spectator. I just can't seem to bring up those emotions necessary to consider one an enemy. It doesn't seem Christian...Satan, however, I do consider an enemy.

If enemy refers to a specific person or people, and it usually does, then it can be considered a metaphor for Satan, the enemy.