What beliefs are prerequisite for practicing Zen?

[Matylda]

Vajrajana was certainly well known in China. Forms of Tantric and Esoteric Buddhism , such as Mantrayana, (Shingon being the Japanese version of Chinese Esoteric Buddhism) were well known in Korea in ancient times, both directly from India and through schools that included it such as Tientai. You can also see this in old Buddhist art in Korea. I don't known how long practice survived, but it would be odd if Korean monks did not study at least some classic texts. Of course, some Korean monks went to China and at least one taught Buddhism in Tibet (check out Buswell's articles on Korean influence through the Chinese cultural sphere).

Generally it does not respond to the original question, but..
There is no any Indian vajrayana transmitted to Korea via China. There are no reports of it like hundered years ago. So as you say they were well known in ancient time, but simply did not survive. Todays esoteric school in Korea is modern development without historical relation to unbroken lineage.
As for chogye what i have seen in manuals of chogye monks was actually from Japanese shingon. In China shingon school called 真言 Zhēnyán was not existing any more during Yuan dynasty. So Mongolian emperors actually were under Tibetan sakya influence.
Chinese do not even recognize Buddhist vajrayana sculptures in there own temples like 靈隐寺 in Hangzhou, which they told me that those are some sculptures from Mongolian time and of their own religion (!).

As for chan sutras, one more thing, they were not yet popular in Tang or Sung dynasties, if they were, for sure there would be clear transmission of those texts within zen lineages to Japan. But it did not happen for over 300 years of intensive zen relation between China and Japan. They became more popular during Ming dynasty when in China zen was in decline and became more syncretic religion with strong pure land influence and other elements, which was strongly opposed before. And in fact they have hardly any connection to zen, though they may be used as some means of education.

[Astus]

As for chan sutras, one more thing, they were not yet popular in Tang or Sung dynasties, if they were, for sure there would be clear transmission of those texts within zen lineages to Japan. But it did not happen for over 300 years of intensive zen relation between China and Japan. They became more popular during Ming dynasty when in China zen was in decline and became more syncretic religion with strong pure land influence and other elements, which was strongly opposed before. And in fact they have hardly any connection to zen, though they may be used as some means of education.

The Perfect Enlightenment Sutra was commented on by Zongmi (780–841). Wonhyo (617–686) commented the Vajrasamadhi Sutra. The Surangama Sutra gained popularity in the Ming Dynasty because of Hanshan Deqing and his fellows, so in Japan the Obaku school should favour it, for instance Tetsugen Doko did lecture on it. Hakuin also taught it in 1756, and Torei makes reference to the sutra in his Inexhaustable Lamp.

As for the supposed decline of Zen during the Ming era, it is quite the opposite, there was actually a great renaissance of Chan (see e.g. Jiang Wu: Enlightenment in Dispute). One of the effects of that was the appearance of the Obaku school in Japan.

[Matt J]

I don't think any beliefs are prerequisite for practicing Zen. If there were, then Zen wouldn't be Zen.

Zen is a special transmission, outside the scriptures, not depending on words and letters, pointing to one's true nature. I don't think this means only words and letters, but no fixed form at all. Some Zen masters have taught using words and letters, and some have taught with shouts, sticks, and bodily movements. The important thing is the result --- pointing to one's true nature.

[Caodemarte]

The orthodox Korean Zen view on beliefs and the practice of Buddhism, and specifically Zen Buddhism, is is that practice and study of Buddhist beliefs go together. So one must study Buddhist beliefs and practice mediation in Korean Zen. Belief is not required, but understanding is regarded as essential to good progress. As a practical matter in Korean and all forms of Zen, great faith that the process is useful, great existential doubt, great determination are considered essential. Following a Chinese development, great anger at being fooled and living in ignorance (this seems to me to be a motivational tool, rather than a necessity) is also sometimes mentioned. Nowhere is belief in any specific theory required, but is often assumed.

[Caodemarte]

Rather hijack this thread I started a new topic, "Tantric Influence in Korea" under "East Asian Buddhism: to further explore this interesting topic.

[Matylda]

The Perfect Enlightenment Sutra was commented on by Zongmi (780–841). Wonhyo (617–686) commented the Vajrasamadhi Sutra. The Surangama Sutra gained popularity in the Ming Dynasty because of Hanshan Deqing and his fellows, so in Japan the Obaku school should favour it, for instance Tetsugen Doko did lecture on it. Hakuin also taught it in 1756, and Torei makes reference to the sutra in his Inexhaustable Lamp.

As for the supposed decline of Zen during the Ming era, it is quite the opposite, there was actually a great renaissance of Chan (see e.g. Jiang Wu: Enlightenment in Dispute). One of the effects of that was the appearance of the Obaku school in Japan.

Actually PE sutra and other 'chan sutras' as you write were lectured by few masters, but it did not pick up untill post Sung China, and did not match popularity of Diamond sutra or Mahaparinirvana.. in China there was opposition towards some sutras including Surangama what evidence one can find in Hokyoki of Dogen, and his informers were Chinese masters. Surangama is popular in Japan but only long mantra, not the sutra text as such. And as I wrote before previous kancho of Mampukuji published it, but not commentary on the sutra. One can hardly find any in Japan.. in cataloges for sure something could be, but there is no popularity... in teachings some parts are used but by very few teachers.. the last one I can recall was Yamada Mumon. But still it came as mouth to ear admonitions when it came to mistakes in experience and interpretation of zazen results. Not as a full scale commentary.

Ming was slight revival of chan, but it could not be any longer compared to late Tang and North/South Sung periods... anyway even in the eyes of Chinese Tang/Sung was golden age of zen, as you must know.. war with Mongolian empire destroyed pretty much power of Chinese buddhism, and with changing dynasties from Yuan to Ming taoists and confucianists took upper hand at court, and many zen temples got into trouble. Including Hanshan himself who was banished.. and at that time zen buddhism became a blend of different schools, and popular believes...
Obaku had its short moment of popularity in Japan, really short, it drew attention since it was so exotic and did not remind of zen from Sung. They had a lot of non-buddhists things as well which still survive in Mampukuji. Taoist offerings from slaughtered animals etc. and non-buddhist temples in the compound of zen monastery... anyway when Japanese monks flew to Obaku in the beginning of its existence in Japan many returned really disappointed.

And later on, Obaku completely lost its lineage, so finally they had to be supported by rinzai, and today all Obaku it is takuju lineage of Hakuin, with few koans added from Ming time.. as for Tetsugen: probably he would not be so well known in Japan or even in Obaku itself, since his power of zen teaching was rather problematic.. but he was great figure due to Tripitaka edition and his devotion to complete it. Moreover he was probably very good person and very human.. what is interesting some of Obaku temples were lost to Jodo-shu including Tetsugen own temple, which was very big in Edo period. Due to pure land teachings also jodo-shu monks were attracted to Obaku. Tetsugen's temple still exists, and has some of the famous 500 arhat figures I think there were made after Tripitaka edition... only little bit more than 100 were saved during the war.

[Matylda]

The orthodox Korean Zen view on beliefs and the practice of Buddhism, and specifically Zen Buddhism, is is that practice and study of Buddhist beliefs go together. So one must study Buddhist beliefs and practice mediation in Korean Zen. Belief is not required, but understanding is regarded as essential to good progress. As a practical matter in Korean and all forms of Zen, great faith that the process is useful, great existential doubt, great determination are considered essential. Following a Chinese development, great anger at being fooled and living in ignorance (this seems to me to be a motivational tool, rather than a necessity) is also sometimes mentioned. Nowhere is belief in any specific theory required, but is often assumed.

Yes, but I think it happened after reforms in Korean zen... so they created education for monks which before did not exist in today's form... it all developed in the XXth century, before there was no chance, since real suppression of buddhism in Korea.. monks were excluded from the capitol which were allowed to enter for the first time in the 90ties of XIX century... so a little bit more than 100 years ago..

[Caodemarte]

In terms of belief, I think Korean Buddhism has a traditional emphasis on intellectual effort combined with meditative effort rather than on specific beliefs. Of course,it seems assume that you will end up believing in the main elements of the Buddhist tradition. On the other hand, there have been campaigns over the years to get Buddhists to stop believing in shamanism (seen as superstition).

Before the attempted suppression of Buddhism the tradition of study and practice was very well established. In fact, Korea produced some of the great scholar/practitioners of Buddhism (some of whom ended up in China). The destruction of the Imjin War (against the Japanese), Japanese colonialism. and the Korean War (and the rise of the North Korean regime) probably had a more devastating impact on Korean Buddhism as they did on Korea as a whole than the attempted suppression during part of the Choson dynasty.

[TaTa]

I am no zen practitioner but i guess that believing in suffering is a good start...

[dharmagoat]

I am no zen practitioner but i guess that believing in suffering is a good start...

We need to believe in suffering as much as a fish needs to believe in water.

[TaTa]

I am no zen practitioner but i guess that believing in suffering is a good start...

We need to believe in suffering as much as a fish needs to believe in water.

Exactly

[Matylda]

suffering is more than obious and is basis for many religions not only Buddhism or zen... therefore people look for salvation and help of God.. however if we talk about zen in its original form something called bodaishin, hotsubodaishin 菩提,　菩提心　or just bodhicitta in sanskrit、 is point and place where everything starts in zen...