David uses the verse to illustrate how the Lord provides rest in green pastures and leads him to still waters. Israel doesn’t have much lush pastureland except when it rains. Sheep need to be guided to green pastures by the Shepherd, or they will be hungry. In addition, sheep do not drink from rushing streams. And it is unlikely that they will seek out clean water and are more likely to drink whatever is nearby. Therefore, a good shepherd leads his sheep to calm, clean water.
The good and faithful Shepherd, Christ, leads and guides His sheep, namely us, in the best way for all of us to follow. As much as He knows our names, He knows our needs; He knows where each of us would encounter dangers and difficulties in our paths – He also knows how to protect us when it is time.
In light of our heavenly Shepherd, how foolish it is to go after the stagnant pools and broken cisterns this world offers, and how foolish to become entangled in the fantasies of this world or sink in the whirlpools of life's disasters.

Dear Heavenly Father, thank you for being all I need. Let me never stray from Your path of righteousness, and may I thirst for You every day and be satisfied in You. Please allow me to keep my eyes on You, our good Shepherd, who restores my soul by making me lie down among green pastures and gently leading me beside the waters of stillness. 
In Jesus's name I pray. Amen.