What does Psalm 23:4 mean?

David could walk through a dark ravine, perhaps even death, fearlessly, because the Lord walked with him. David explains his lack of fear because "you are with me." It is interesting to observe that the "shadow of death" drew David closer to the Lord. He addresses the Lord as "you," whereas in the peaceful places he called the Lord "he."

A shepherd in Bible times carried a rod and a staff to protect his sheep. The rod was a cudgel: a short, thick, heavy stick similar to what modern people might call a baton or mace. This was worn at the shepherd's belt. The staff was a long, lightweight pole with a curved end—a crook—that the shepherd used to move, count, and examine the sheep at evening when they returned to the fold.

Both the rod and staff were used as weapons to protect the sheep. David trusted the Lord to protect him, just as a shepherd protected his sheep from any attacking animals. Jesus, the Good Shepherd, is with believers at all times (John 10:11, 14). He promised to be with us always (Matthew 28:20). He is with us when we walk over rough ground as surely as He is with us "beside still waters" (Psalm 23:2). Jesus said, "I give them eternal life, and they will never perish, and no one will snatch them out of my hand" (John 10:28).