To sit in meditation before a closed door, as though it were a heavy door of bronze—and one sits in front of it with the will that it may open—and to pass to the other side; and so the whole concentration, the whole aspiration is gathered into a beam and pushes, pushes, pushes against this door, and pushes more and more with an increasing energy until all of a sudden it bursts open and one enters. It makes a very powerful impression. And so one is as though plunged into the light and then one has the full enjoyment of a sudden and radical change of consciousness, with an illumination that captures one entirely, and the feeling that one is becoming another person. And this is a very concrete and very powerful way of entering into contact with one’s psychic being.
Ref : Questions and Answers 1955