“The Lord is my Shepherd I shall not want.”
The responsibility of the shepherd is to cause the flock to eat, drink and rest. Jesus says in John 10:`11 “I am the good shepherd; the good shepherd giveth his life for the sheep.” His life is the diet of His sheep.
Jeremiah 23:4 says “And I will set up shepherds over them which shall feed them; and they shall fear no more, nor be dismayed, neither shall they be lacking, saith the Lord.” And Jesus says in John 6:55-56 “For my flesh is meat indeed and my blood is drink indeed. He that eateth my flesh, and drinketh my blood, dwelleth in me, and I in him.” The sheep feed off of the Shepherd because the Shepherd gives them His life to feed upon. His life is nourishment to the sheep.
However, the sheep must take in what the Shepherd gives. As the sheep feed upon the shepherd’s life they find that they are not afraid or dismayed because of the things that are going on in the world neither do they lack anything. That’s why David said “The Lord is my shepherd I shall not want” he understood that the Lord was supplying all that he needed out of His life. Philippians 4:19 “But my God shall supply all your need according to His riches in glory by Christ Jesus.”
When you are full of Jesus you have no room to take in fear, doubt, anxiety or stress. The only thing you want to do is rest. Feed upon Jesus and rest.