Psalm 23 comments from D. L. Moody's Bibles:

Psalm 23:1     "The Lord is my Shepherd I shall not want" — a lean scraggy sheep with torn limbs & tattered fleece, would be small credit to the shepherd's care; but unless we will wander from Him, and will not remain restfully under His protection, there is no fear of such ever being our lot.

No Lion or Bear  can ever surprise our ever-watchful guardian or overcome our Almighty Deliverer. 

 

Psalm 23

Beneath me: green pastures.
Beside me: still waters.
With me: my Shepherd,
Before me: a table.
Around me: mine enemies.
After me: goodness and mercy.
Beyond me: the house of the Lord. 

Psalm 23 a.

    This suggests the rest into which our Good Shepherd leads His flock. Life is not all toil. God gives us many quiet resting places in our pilgrim way. Night is one of these, when, after the day's toil, struggle, and exhaustion, we are led aside, and the curtains are drawn to shut out the noise and He giveth His beloved sleep, in sleep giving the wonderful blessings of renewal. The Sabbath is another of these quiet resting places. God would have us drop our worldly tasks, and have a day for the refreshing of both body and soul. . . . . 

    Friendship's trusts are also quiet resting places, where heart may commune with heart, where Jesus comes, too, unseen, and gives His blessing. All ordinances of Christian worship—seasons of prayer and devotion, hours of communion with God—are quiet resting places. Far more than we are apt to realize do we need these silent times in our busy life, needing them all the more the busier the life may be. — J. R. Miller