" The tantric beginner is advised to eat, drink, and have sexual relations according to the customs of his own country until he attains the mantra-siddhi or the gnosis-siddhi and thereby becomes a tantric yog. .... However, once a tantric adept attains the mantra'siddhi or the gnosis-siddhi (jruma-siddhi), he is allowed to eat and drink and have sexual relations not just according to the customs of his country and social class but just as he pleases, because he has transcended the distinction between the allowed and prohibited, the suitable and unsuitable, and no one is able to object or harass him .
from "The Inner_Kalacakratantra A Buddhist Tantric View of the Individual"
This kind of doesn't apply to us at all (at least not literally) because we are outside the Indian caste system and whatever system mapped animals for meat to tantric deities. This is a really old school quote that basically just means "until you attain some degree of realization, continue to conform to social norms."
How should I understand this quote?
once a tantric adept attains the mantra'siddhi or the gnosis-siddhi (jruma-siddhi), he is allowed to eat and drink and have sexual relations not just according to the customs of his country and social class but just as he pleases, because.. no one is able to object or harass him
Once the person develops some form of magic powers (mantra siddhi) or insight (gnosis siddhi) then they can transcend the restrictions of their society. Gnosis siddhi in this context seems to mean really a deeper degree of enlightenment rather than just insight. So a person like Virupa or Milarepa or Tilopa as some examples.
Why nobody is "able" to object or harass him?
Because s/he doesn't care.
Because he is capable to display in public such siddhis, and everybody will understand that it is a real tantric adept? Is tantrism really so pragmatic?
Could be. More likely with some degree of real enlightenment they don't care. And if they are able to perform magical feats then they might be able to protect themselves from harm (tantrism is so pragmatic on that level).
What does Vesna Wallace have to say about this passage? This is really just saying continue with your local customs until you have some realization. Of course if one of your local customs is cannibalism then you might have to reconsider something that that immediately. But the context was the normal caste structures of India circa, what?, 700-800 AD.
_________________Kirt's Tibetan Translation Notes
"Only you can make your mind beautiful."
HH Chetsang Rinpoche