He makes me lie down in green pastures, He leads me beside quiet waters,
Life is just tough! Each day you face things that are stressful, challenging, tempting, painful, and trying to your faith. Unless you live in a dark room with no contact with the outside world, there is no way to avoid the challenges of life. But there is a way to deal with them, and that is through your relationship with Jesus Christ.
If you had been alive when David wrote Psalm 23, you would immediately understand what it was he was talking about, for everyone knew shepherds and what they did. One thing a shepherd has to be on the lookout for is fast moving water. Sheep get so excited about a refreshing drink they can easily end up falling in. When this happens, their wool gets soaked and they quickly drown. It is the shepherds job to make sure that the streams their flock drinks from is slow moving and shallow.
David is testifying to God being our shepherd. Even though there are dangers associated with sheep getting a drink, there is no way to avoid the need for water. Just as there are dangers and struggles we will face in everyday life, God, like the shepherd, watches over us, steering us clear of those dangers and preparing to catch us when things go wrong.
Sheep have a great trust in their shepherd. They can tell his voice and they know he can be trusted. In a former church I had a youth whose family raised sheep, and when I would walk in the pen they would run from me. When he walked in, they came right up to him. That trusting relationship was one built over time and through experiences.