Is there anything akin to 'Jhana' in Zen Buddhism? I have read about 'Jhana' in Ajahn Brahm's book, 'Mindfulness, bliss and beyond'. It looks like, from his teaching of Theravada Buddhism, 'Jhana' is a pre-requisite to attain 'Nirvana'.
I want to ask, is there anything similar to 'Jhana' in Zen.
From my readings it does not seem it's 'Satori'.
Zen and Jhana are the same word. Jhana is a word in the original spoken language. In Sanskrit it is written as Dhyana. Channa or Chan is how it came to Chinese language, and Zen is how it subsequently came into the Japanese (in English transliteration).
Jhana or Zen means the mind of meditation.
If you ever heard the phrases &quot;attain the state of Zen&quot; or &quot;show me your Zen&quot; - that refers to the same practice/result as Jhana. (The popular image that it refers to being a crazy wacko is a modern misunderstanding. &quot;Attaining Zen&quot; is breaking through to spontaneous clarity as a result of quality meditation practice.)
Of course if you are looking for the one-to-one Zen equivalents of each of the four jhanas or the eight jhanas, you will be disappointed - because such cut-and-dry categorization of practical experience would be very much against the spirit of Zen which emphasizes the first-hand discovery and learning-by-doing while avoiding the step-by-step instructions a-la Theravada as a dangerous trap for the mind. So in Zen everything is a little more fluid and the practice of meditation is not split in discrete phases. Nevertheless, the kind of meditation practiced in Zen is an authentic Jhana, functionally equivalent to the fourth Jhana of Theravada Buddhism.
Now, if you expand your scope beyond Zen and take a look at Vajrayana, it has two types of meditation closely associated with the first and second/third jhanas. I'm talking about Generation-phase and Completion-phase meditations correspondingly.
I imagine someone daring might combine the traditions and practice the Generation-, then the Completion-, then the Zazen/Shikantaza-meditation with great results.