IT IS A CURIOUS point about our Lord's teaching, or about that part of it at any rate which has been preserved for us by St John, that he is always treating the things of earth, the material things of sense which are familiar to us, as unreal, as mere shadows and appearances, while the true realities, of which these earthly things are but copies, are in heaven. It is our habit to think the other way; to assume that our own flesh and blood, our food and drink and all the comforts we enjoy, are solid realities; heaven is something distant and shadowy - we believe that we shall be happy if we attain to it, but we cannot imagine how, because it all seems so remote from this real world of our experience ...
He calls us away from a world of shadows into a world of realities; from the perplexities of our earthly citizenship to a city which has foundations whose builder and maker is God.
- Ronald A. Knox