It is a very special day for all practitioners of Buddhism, because it is the anniversary of three important events in Lord Buddha’s life.
First of all, it is the anniversary of Lord Buddha being born in our world.
Secondly, under the Bodhi Tree, he attained what we all wish and hope to attain: perfect enlightenment. There are many different types of liberation known throughout the world, over the centuries and millennia – they all have their own philosophies, theories, conclusions, and ideas about various forms of liberation, but the one that Gautama attained under the Bodhi Tree is known as the perfect enlightenment, the absolute liberation. So that’s the second event.
And the third one is known as the Parinirvana, meaning that the present conditions that we have – the external or outer conditions, which are the world we live in; the inner conditions, such as our thoughts and our own body; as well as the secret conditions, our own consciousness – that all of these are compounded phenomena, and from the moment something is compounded, it is a given that at one particular time whatever compounded phenomenon was there will be subject to impermanence; it will dissolve. And so, in order to demonstrate that, to show that, the Buddha passed away into perfect enlightenment, and in doing so he left with a great teaching, showing that all phenomena come to an end. It is neither good nor bad; it is natural.
So these three events sum up the whole teaching of the dharma, everything that we as practitioners are trying to understand and achieve.