Question: What are the esoteric (secret) teachings (密[秘]教) in Buddhism?
Answer: In terms of the Buddha’s teachings, as the opposite of the exoteric (revealed) teachings (显教), the esoteric teachings have ‘hidden’ and complex meanings, principles or truths, even after they were taught. They were not deliberately ‘hidden’ by the Buddha. In fact, for benefitting us, he revealed them as much as he could when it was skilful to, with them otherwise completely ‘hidden’. They are only as if ‘hidden’ to the unenlightened, with them naturally and fully revealed upon enlightenment.
For instance, say the formula E = mc². Before its discovery, it is as if ‘hidden’. Even after being revealed, it is still somewhat ‘hidden’, as in mysterious, to those yet to understand how this principle is arrived at. Yet, the formula works. Only upon deeper study of physics, can one fully appreciate how it is arrived at, and how it does represent the truth of the relationship between energy and matter.
Likewise, for mantras (咒) and dhāraṇīs (陀罗尼), which are esoteric in nature, including Amitābha Buddha’s (阿弥陀佛: Āmítuófó) name, to the extent that we are unenlightened, they have seemingly ‘mystical’ and profound properties. Yet, even without fully understanding its benefits, reciting it still works, with their workings fully understood when we become Buddhas personally.
It is not that esoteric meanings were not fully disclosed, but that they are too profound to be spoken of, such that they have to be realised. For example, exactly how mindfulness of Āmítuófó’s name creates all kinds of blessings is known only when we become Buddhas. The best the Buddha could do was reveal some of the many blessings to us, and encourage us to practise accordingly. Thus, the Buddhas always reveal all they can, while the hidden have to be realised. The esoteric is so only to non-Buddhas; it is exoteric only to the Buddhas.
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