Metaphysically understood, the “inner chamber” is the spiritual consciousness within the mind and soul of man, it is also called “the secret place of the Most High.” Having shut your door. Shutting the door of the mind is closing out the thoughts of the outer world from one's consciousness. Pray to your Father who is in secret. The spiritual center within every one of us is hidden and secret from the outer consciousness. When we, in the silence, center our attention upon Spirit within us, we make contact with the universal Spirit in which we live, move, and have our being.
Fillmore Study Bible The New Testament Metaphysically Interpreted