to an incorruptible and undefiled inheritance that doesn't fade away, reserved in heaven for you,

 This passage begins with the idea of rebirth; the Christian is a man who has been reborn; begotten again by God to a new kind of life. Whatever else this means, it means that, when a man becomes a Christian, there comes into his life a change so radical that the only thing that can be said is that life has begun all over again for him. This idea of rebirth runs all through the New Testament. Let us try to collect what it says about it. 