King James Version text:

Lord, how are they increased that trouble me! many are they that rise up against me.
Many there be which say of my soul, There is no help for him in God. Selah.
But thou, O LORD, art a shield for me; my glory, and the lifter up of mine head.
I cried unto the LORD with my voice, and he heard me out of his holy hill. Selah.
I laid me down and slept; I awaked; for the LORD sustained me.
I will not be afraid of ten thousands of people, that have set themselves against me round about.
Arise, O LORD; save me, O my God: for thou hast smitten all mine enemies upon the cheek bone; thou hast broken the teeth of the ungodly.
Salvation belongeth unto the LORD: thy blessing is upon thy people. Selah.

I’m still no Isaac Watts, but this one turned out better than some of my other attempts. Perhaps because I had one of my favorite tunes in mind:

Psalm 3
Lord, how my enemies
rise up each day.
All of the world tells me:
“God shall not save!”
But I know better
for You are my shield;
To your protection
my safety I yield.

I cry aloud and you
answer my prayer;
When I am sleeping,
I know you are there.
Thousands of foes shall not
cause me to fear;
God shall sustain me,
to Him I draw near.

Rise and deliver, O Lord,
I beseech;
Strike down my foes, keep me
safe from their reach.
Father in Heaven,
deliver me now;
Save me, for humbly
before you I bow.