In the OT, the shepherd and the sheep is a metaphor for the rulers and people of Israel. Jesus appropriates the metaphor to himself and his disciples in his parable in John 10. He describes himself as the 'gate' of the sheepfold, indicating that he is the one who provides security for his people against the powers of sin and evil. Looking forward to the Cross, he claims to be the 'good shepherd', who 'lays down his life', so that his people 'may have life'.