Dear Dew Drop,
Firstly, welcome to the PoF website. HAH, the infamous double. Rudolf Steiner speaks to the double in many of his lectures and especially in his book “Occult Science – An Outline, see therein Chapter V, Knowledge of the Higher Worlds (concerning initiation).” He also speaks to the double in his lecture series on “Geographic Medicine, - Lecture II, the Mystery of the Double.”
The double is also spoken to in relationship to the 1st Guardian of the Threshold, in his book “Knowledge of the Higher Worlds.”
From my understanding, as a pupil of Spiritual Science, if we are sincerely on the path, with reverence and dedication sooner or later we will be presented with our own double, but not until we are ready (can be a pretty scary thing to look at), and have experienced a sound and proper spiritual science training. This will only happen when we are able to enter the spiritual world correctly, experiencing a clear distinction between the surrounding spiritual world and ourselves, and this requires genuine self-knowledge and understanding. All of our sympathies and antipathies and other soul qualities are grouped around our Ego and are the attraction for our Karma. From Steiner: “this Ego, with all its encumbrances, must necessarily be the first picture that confronts the human soul on ascending into the world of soul and spirit. According to a certain law of the spiritual world, this — the man's “Double” — is bound to be the very first impression man receives on entering the spiritual world.”
Facing our own double requires courage and strength. If you read the comments on this website, you will know that we are all struggling on the spiritual path. It would appear, we are, for the most part, caught up in our own Ego and therefore we would not be able to bear the truth of our double, thus most of us have not seen our double (but I imagine there are some on this website who have). I would also imagine that one soul trait acquired (through hard work) by the individual that may indicate this person has experienced (seen) their double, would be genuine humility. The 1st Guardian of the Threshold does not allow us to enter the spiritual world unless we are truly ready. From Steiner: As far as his or her life in the physical world is concerned, the moment the human being begins to draw near to the world of soul and spirit, the Double immediately makes himself invisible and therewith also conceals from the individual the whole soul-and-spirit world. The Double stands in front of it like a Guardian, forbidding entrance to those who are not yet competent to enter. He may therefore rightly be called “The Guardian of the Threshold of the World of Soul and Spirit.”
Steiner also speaks to the double entering the human body as we incarnate, remaining with us throughout our life. It is explained by Steiner that if not for the mystery of the Christ event at Golgotha we might not be able to overcome our double, but it is through this mystery that we have been given what we need to overcome our double. It is also through the mystery of Golgotha that we are able to develop our experience of our higher "I" (much has already been shared on this website about the higher "I" [see Kristina Kaine]).
Steiner also states: “This double about which I have spoken is nothing more or less than the creator of all physical illnesses that emerge spontaneously from within; and to know the double fully is organic medicine, illnesses that appear spontaneously from within the human being come not through outer injuries, not from the human soul, they come from this being. He is the creator of all illnesses that emerge spontaneously from within; he is the creator of all organic illnesses.”
In Lecture II of Geographic Medicine, Steiner speaks to the geographic double of America. I will say just a little here because I think this is something you should read for yourself (try "Steiner Archives" on the internet, http://www.rsarchive.org). I will add here though that we have to remember also that the Etheric Christ is also deeply embedded in the geographic area that is North America (as also for the whole earth).
Good luck with this and best regards.
Cheers,
Patri