
Dogen instructed:
Impermanence is swift; birth and death are vital matters. During this short life, if you wish to study or practice some activity, just practice the Buddha-Way and study the Buddha-dharma. Since literature and poetry are useless, you should give them up. Even when you study the Buddha-dharma and practice the Buddha-Way, do not study them extensively. Needless to say, refrain from learning the Exoteric and Esoteric scriptures of the teaching-schools. Do not be fond of learning on a large scale, even the sayings of the Buddhas and patriarchs. It is difficult for us untalented and inferior people to concentrate on and complete even one thing. It is no good at all to do many things at the same time and lose steadiness of mind.
This passage from Dogen gives me some difficulty since it seems to superficially state that all activities other than Buddhism are a waste of time and should be avoided. Which, in a way, he is but it should noted that these discourses are meant for monks and not lay-persons. So, while it needs to be understood in that context, we can play with the meaning some to provide insights for the lay-practitioner (like myself).
In some translations, I have seen the statement "just practice Buddhism" which would infer the study of scripture and the Pali canon but then Dogen goes on to say not to study those things (or at least not to dive to deeply into them). So where does Dogen's true meaning lie? I think in the translation I have above with the statement of "just practice the Buddha-Way...and Buddha Dharma" the meaning is in your daily life to practice (whatever it be...dishes, zazen, marketing reports) within the framework of the Buddhist Ideal - with compassion.
Some will disagree with this but most of them have a desire to study the almost inexhaustible Buddhist Canon. The simple fact is that as lay-practitioners, we do not have the time to do this. I can't study the Tripitaka or the Lotus Sutra or the Pali Canon while doing the duties of the Householder. So I take my Dharma where and when I can get it. Mostly that will include the practice of Mindfulness and Compassion in daily activities. That is what I draw from the closing line - "It is no good at all to do many things at the same time and lose steadiness of mind."