One day Dogen instructed,
An ancient has said, “Associating with a good person is like walking through mist and dew; though you will not become drenched, gradually your robes will become damp.”1 This means that if you become familiar with a good person, you will become good yourself without being aware of it.
In ancient times a boy who attended Mater Gutei (Judi)2, without noticing when he was learning or when he was practicing, realized the Way because he had served as a personal attendant to the master who had been practicing for a long time.
Similarly if you practice zazen for a long time you will suddenly clarify the Great Matter and will know that zazen is the true gate [to the buddha-dharma].