At the time it was written, shepherding was a very common activity. Sheep are nearly defenseless against predators, and they scare easily, especially in groups. Let the Lord be your shepherd and guide you to more tranquil places. He will lead you on the right path if you are willing to follow. Think of the consequences for a sheep: follow and be protected, eat, rest, and survive or stray and be alone, starve, fear, and die. The choice is easy.
And we pray:
O Lord my Shepherd, I shall not want. All I have needed Your hand have provided. You have protected me, acting as my rock and shield against all evil. Alas, God – my Father in Heaven, I have sinned, allowing evil to enter my heart even whilst You stood guard against it. Forgive me for this, and know that my pure Love for You shall not wane. I pledge all of this in honor of my service to You and Your Son, Jesus Christ. Amen.