Known as Bodhi Day, the Buddha’s day of enlightenment is called Rohatsu in Japan and is celebrated there on December 8th.
Here is a page from a Buddha comic book illustrating the event. It is published by the Indian company Amar Chitra Katha, which publishes a number of fascinating religious comic books—not only about Hinduism and Buddhism, but about Sikhimism, Zorostrianism and others.
In stillness, mind and object merge in realization and go beyond enlightenment. Thus, in the state of receptive samadhi, without disturbing its quality or moving a single particle, you engage the vast buddha activity, the extremely profound and subtle buddha transformation.
Grasses, trees, and lands that are embraced by this way of transformation together radiate a great light and endlessly expound the inconceivable, profound dharma. Grass, trees, and walls bring forth the teaching to all beings, including common people and sages; all beings in response extend this dharma to grass, trees, and walls. Thus, the realm of self-awakening and awakening others invariably holds the mark of realization with nothing lacking, and realization itself is manifested without ceasing for a moment.
This being so, the zazen of even one person at one moment imperceptibly accords with all things and fully resonates through all time. Thus, in the past, future, and present of the limitless universe, this zazen carries on the buddha’s transformation endlessly and timelessly. Each moment of zazen is equally the wholeness of practice, equally the wholeness of realization.
This is so not only while sitting; like a hammer striking emptiness, before and after its exquisite sound permeates everywhere. How can it be limited to this time and space? Myriad beings all manifest original practice, original face; it is impossible to measure. Even if all buddhas of the ten directions, as innumerable as the sands of the Ganges, exert their strength and with the buddha wisdom try to measure the merit of one person’s zazen, they will not be able to fully comprehend it.
Dogen Zenji, On the Endeavor of the Way
Treasury of the True Dharma Eye