In the five phases outlined by Tozan & Underhill (see previous postings), there are two dark nights and they are quite different from each other.
Phase one is a glimpse of something beyond our exclusive human identity. It often initiates a period of practice (although the first three phases can also come out of the blue).
Phase two is the dark night of the senses. This is where we disengage from an exclusive identity with/as a human self and a dualistic view. This phase can be experienced as being pulled apart, dismembered, dying, and so on. There is a sense of complete disintegration, and pain and suffering from - naturally - resisting this process.
At phase three, we identify as the absolute, Spirit, Big Mind/Heart. This is a full blown awakening with the usual non-dual view, immense clarity and insights, compassion and so on. It is the birth of the Buddha, although still an infant Buddha. There may be a sense of it being special and an accomplishment, and we may be somewhat stuck as the absolute.
Phase four is the dark night of the soul. This is a process of disengaging with our identity as the absolute, as Big Mind/Heart. Here, everything we found comfort in at phase three is taken away from us. We are utterly human again, and in an utterly human misery. Our life falls apart in many or all areas: we (appear to) loose connection with the absolute, our health, relationships and standing in the world may go down the toilet, our clarity and insights are gone, our heart may close up, any hope is gone, any strength is gone, any willpower is gone. It is a profoundly humbling phase.
Phase five is the new integration of the relative and the absolute, our human self and Big Mind/Heart. This time, it all returns in a way that seems utterly ordinary and unremarkable. We are now familiar with the relative (from phase one, two and four) and the absolute (from phase three), and they can be integrated in a more grounded and mature way.
While we in phase one and two were identified as a human being, and in phase three as Big Mind/Heart, our identity is now not fixed anywhere in particular. It moves more fluidly among the personal and transpersonal, between the relative and absolute.
In our daily life, there is a deepening maturing, clarification, familiarity with ourselves as human and Big Mind/Heart, and fluidity between the relative and absolute.
While phase three is called the brilliant sun of enlightenment - radiant and remarkable to us and others, this is the hazy moon of enlightenment - far more ordinary, grounded and mature.