Those who regard worldly affairs as a hindrance to buddha dharma think only that there is no buddha dharma in the secular world; they do not understa… - Dōgen

A billion worlds can be sat through within a single sitting.

The Buddha said, "Elements come together and form this body. At the time of appearing, elements appear. At the time of disappearing, elements disappear. When elements appear, I do not say "I" appear. When elements disappear, I do not say "I" disappear. Past moments and future moments do not arise in sequence. Past elements and future elements are not in alignment. This is the meaning of ocean mudra samadhi." Closely investigate these words by the Buddha. Attaining the way and entering realization does not necessarily require extensive learning or realization. Anyone can attain the way through a simple verse of four lines. Even scholars of extensive learning can enter realization through a one line verse.

All the Buddhas, whether in this world or in other quarters, in the western heaven (India) or the eastern earth (China), equally held the Buddha-seal and altogether enjoyed the supreme style. They were fully devoted to this total sitting (shikantaza) and were totally installed in this unmoved state. Even though there are a thousand differences and a million nuances, they engaged devotedly in practicing zazen and realizing the Way.