Buddha-nature is a fundamental dharma and a number of sutras discuss its universality, yet none of them actually use the term, “Buddha-nature.”
The Surangama Sutra, for instance, expounds the principle of Buddha-nature in terms of “pure” mind and uses the metaphor of light.
The Buddha said, Ananda and all of you should know . . . that living beings, since the time without beginning, have been subject continuously to birth and death because they do not know the permanent True Mind whose substance is, by nature, pure and bright.”
Later, the Buddha explains that living beings have lost sight of the light, the original brightness, even though it shines within them all day long, and because they remain unaware of it, they make the mistake of “entering the various destinies.”
The Surangama’s essential point is how to make people recognize their Buddha-nature. How much can you see of the Buddha-nature inside of you?
The sutra is a teaching for the Buddha’s cousin, Ananda; it is his sutra. The title, “Surangama,” means “indestructible.” Because the light is always shining within us, whether we see it or not, it is, in a sense, indestructible or unyielding. When we are able to see our Buddha-nature, and not lose sight of it, the “light” becomes the basis for the way we live and act out our life, and then this becomes our own indestructible sutra.
Not only is the purpose of meditation to cultivate a peaceful mind and rest our minds in the now, it is also a tool to help open our eyes to our Buddha-nature. When the Buddha said to his disciples “be a lamp unto yourself,” he was telling them not to seek the light outside of their own lives, look within. In This Light in Oneself, Jiddu Krishnamurti wrote,
One has to be a light to oneself; this light is the law. There is no other law. All the other laws are made by thought and so are fragmentary and contradictory. To be a light to oneself is not to follow the light of another, however reasonable, logical, historical, and however convincing.
You cannot be a light to yourself if you are in the dark shadows of authority, of dogma, of conclusion. Morality is not put together by thought; it is not the outcome of environmental pressure, it is not of yesterday, of tradition.
Freedom is to be a light to oneself; then it not an abstraction, a thing conjured up by thought.”
So, don’t lose sight of your light.