To spot the darkness within, there must be light.
I was reading a book called Dark Night of the Soul, by Saint John of the Cross, and this idea of light revealing darkness never left me. There's a lot of grace in this perspective.
Before we get into that though, it’s worth mentioning this; in all religions or eastern traditions, the end goal of the human experience is union with the divine, nirvana, or samadhi etc.
Another way of understanding this is to say the end goal of human evolution is a sense of wholeness, and this sense of wholeness could be labeled as oneness, or unity.
In this way of being, the individual ceases to be an individual, and becomes one with all; the sense of separateness dissolves. For that to happen though, the ego has to ‘die’. In Zen, they call this ‘the great death’, the Sufi’s call it ‘the holy war’, where the Nafs (ego) is annihilated, one has to die before the body dies.
It's obviously a painful experience to die before you die, to die while alive, to totally detach from the senses. Not only does one detach, but also the root of all sensual desire must be uprooted, so desire hardly exists anymore. That truly is a form of death. Imagine living in a desert, all alone, with only water and bread, and no desire to even leave, its something like that.
This process of purification, or purgation as St. John calls it, has also been called the hero’s journey by anthropologists, or individuation by the psychologist Carl Jung.
Here’s a nice way of looking at it.
Back to St. John.
What St. John was saying is although at times we suffer, and suffer dearly, we should always rest in the fact that suffering, or darkness, can only manifest in light. In other words, there would be no darkness to start with if the light of consciousness wasn't present, 'In darkness, and secure'.
To better explain that, we could say that for us to truly grow, to uproot the ego or shadow and all associated fear, the light of consciousness directs itself towards the baggage or darkness that lies within our psyche, and only then do we learn how to deal with it, and finally transcend it and all associated suffering.
Its like reality, via suffering, is trying to wake us up to the essence that lies within.
I think what St. John was trying to say was that darkness and light, are one and the same, partners that work hand in hand, that lend a hand, that guides us all the way back home.