The Lord is my Shepherd. So David wrote.
He would know what that meant. Being a shepherd himself he would know what it meant to call the Lord his Shepherd.
Sheep are needy creatures. They fall down and don't know how to get up. They charge each other and butt heads and deliver wounds in the head because their wool causes them to sort of stick rather than graze off each other. They foolishly follow each other - not always to good and safe places. If they wander off, they can't find their way back to the herd. No wonder the shepherd needed to help those who were cast down and couldn't get up; anoint heads with oil so the butting heads wouldn't cause injury but rather slide off each other; stay close to the sheep to keep wandering off to a minimum; leave the sheep to search for the one who got lost.
They are quite helpless creatures. David knew this.
So to compare himself to a sheep was quite profound. To call God his Shepherd was quite lovely. David once wrote, “Yet I am poor and needy; may the Lord think of me. You are my help and my deliverer; O my God, do not delay.” We all need guidance. We all need direction. We all need help, in this life. It is a good thing to recognize one’s neediness, for this realization puts one in position to be guided, directed, and helped. Only the needy know they need a shepherd. Only those who realize their need for guidance can be guided.
Falling down, wounding myself and others, getting lost. Sounds like things I do. I, too, need this Shepherd. And He is mine!!!