Who wrote this line the lord is your shepherd you shall not want?

David, who would be king of Israel, wrote the line "The Lord is my shepherd; I shall not want." (KJV), which is recorded in Psalm 23 in the Holy Bible. It is especially significant since he himself was a shepherd and knew the duties of a good shepherd; take care of the sheep, watch the sheep, protect the sheep from harm (wolves, lions, bears, etc.). He recognized that the Lord, being his shepherd, would make sure that all of his needs would be met, so that he would have want of nothing.