It is absolutely AMAZING that this article makes absolutely NO mention of probably the MOST important element of Jung's biography : the fact that he was part of an extended family of Protestant pastors, his own father being one.
I will get back to this point.
I will probably NOT read Jung's diary. For the simple reason that I consider reading OTHER PEOPLE'S spiritual diaries to be a waste of time.
Jung had his life. I have mine. And NO ONE, absolutely no one, can offer any kind of spiritual mentorship IN A BOOK.
My life "journey" greatly parallels Jung's. I too have "descended" (or risen ?) into madness. I am intimately familiar with it. Once it terrified me to contemplate this fact. No longer. Madness is a fundamental part of the human experience.
It does not weaken or destroy us. But... being afraid of it severely hampers our ability to reap as much "wealth" from it as we could.
Twenty years before Carl Gustav had his experience (1913), Daniel Paul Schreber had his (1893). And he too, wrote a diary. It's called "Denkwurdigkeiten eines Nervenkranken", loosely translated as "Memoirs of a Nevropath", (commented by Freud in "Five psychoanalytic Case Studies"). The book is a detailed, albeit almost incoherent, account of Schreber's persecution by a God with whom he has a voluptuous relationship. Schreber's madness started with a prescient dream in which he "thought" how tempting it would be to be a woman being penetrated, and during orgasm.
"The Interpretation of Dreams" by Sigmund Freud (1899) contains many highly detailed accounts by Freud of his own particularly rich dreams. Freud, too, was very worried about being or going mad. It obsessed him. The book in its own way, is Freud's diary of his spiritual search.
So... the connect with Protestant pastors ?
Jung's theories, and his way of presenting them, are a resurrection of Catholicism's unbelievable intuition about the importance of iconic thought vs. abstraction.
The Catholic Church's cult is/was filled with pictures, pictures that tell a story. Beautiful pictures. And... the very idea of transsubstantiation is an attempt to harness "pagan" magic into the Christian religious experience.
PROTESTANTISM is extremely hostile to all of this. Iconoclasm... initially refers to the breaking of images, and when the Protestants went on rampages through the European countryside, they tore apart the "idols" (i.e. pictures and statues...) in the Catholic churches.
Symbolism is a... WEAKENING, and a rationalisation of mystical experience, which can conventiently become logical and rational. But... with a definite loss of power.
I am neither Jungian nor Freudian at this point. I have my own point of view on all of this. I do not believe in the collective unconscious. What I do believe is... that our language carries within it all the seeds of our ancestor's history, and the history of their/our ideas. When we speak, and think, this history reactualizes itself and makes its influence felt. I also see the attempt to "interpret" our dreams as a dangerous tendency to extend the realm of interpretation, an ever dangerous activity, into areas that would best be left... as untouched sanctuary.
I recommend Robertson Davies "The Deptford Trilogy", book 2, "The Manticore", for a very very perspicacious attitude towards Jungian (and/or Freudian...) psychoanalysis.