The reality of the world could be called self-secret. Something spiritual or mystical in this sense means something that strikes the truth. True spirituality is an absence of frivolity, an absence of belief in good and bad in the religious sense, an absence of religiosity. It is that which is contained in the living situation, which speaks truth, which reminds you of the natural situation of things as they are.
"The Myth of Happiness" in Work, Sex, Money: Real Life on the Path of Mindfulness
by Chögyam Trungpa Rinpoche, pages 37 and 38.