The prophesies in the Old Testament (Ezekiel) speak of a good shepherd; someone to lay down his life for the sheep he considers his.  Conversely, the sheep know their shepherd and follow no other.  In the New Testament, Jesus explains:  "I Am the Good Shepherd.... I Am the Gate.... I come so that they may have life."  Jesus represents safety, security, authority and power.  He will save His sheep, and they will be safe and secure.  He also came to save all -- every person, every race, nation, etc., not just the "sheep" of Israel.