“While the thief comes only to steal and kill and destroy, Jesus comes that they may have life, and have it to the full.
This is a proverbial way of insisting that there is only one means of receiving eternal life (the Synoptics might have preferred to speak of entering the kingdom, although entering into life is also attested there), only one source of knowledge of God, only one fount of spiritual nourishment, only one basis for spiritual security—Jesus alone.
The world still seeks its humanistic, political saviours—its Hitlers, its Stalins, its Maos, its Pol Pots—and only too late does it learn that they blatantly confiscate personal property (they come ‘only to steal’), ruthlessly trample human life under foot (they come ‘only … to kill’), and contemptuously savage all that is valuable (they come ‘only … to destroy’).
Jesus is right. It is not the Christian doctrine of heaven that is the myth, but the humanist dream of utopia.”
–D.A. Carson, The Gospel according to John (The Pillar New Testament Commentary; Leicester, England; Grand Rapids, MI: Inter-Varsity Press; W.B. Eerdmans, 1991), 385. Carson is commenting on John 10:9-10.