In other words ...
Dogen responds, "You still don't get it, silly boy? Let me say it again ... Zazen is enlightenment itself, Zazen is enlightenment realized here and now. Even a beginner's Zazen is original enlightenment made manifest. We are not waiting for enlightenment, we are instead "doing enlightenment" right here. Where one goes, the other is ... without a gap.
Got it now? Got that you always had it?
As for the practice of Zazen, people who have not yet realized buddha-dharma should attain enlightenment through practicing the way of Zazen. But what could those who have already clarified the true buddha-dharma expect from doing zazen?"
Although it is said that one should not relate dreams to fools and it is useless to give oars to mountain folks, I give you further instruction. Thinking that practice and enlightenment are not one is no more than a view that is outside the Way [that is deluded]. In buddha-dharma, practice and enlightenment are one and the same. Because it is the practice of enlightenment, a beginner's wholehearted practice of the Way is exactly the totality of original enlightenment. For this reason, in conveying the essential attitude for practice, it is taught not to wait for enlightenment outside practice. This might be so because [this practice] is the directly indicated original enlightenment. Since it is already the enlightenment of practice, enlightenment is endless; since it is the practice of enlightenment, practice is beginningless. Therefor both Shakyamuni Tathagata and the Venerable Mahakasyapa were accepted and used in the practice of enlightenment, and in the same manner Great Teacher Bodhidharma and Great Ancestor Daikan [the Sixth Ancestor] were pulled and turned in the practice of enlightenment. Traces of dwelling in and maintaining buddha-dharma are all like this. ...
From: Talk on the Wholehearted Practice of the Way - Kosho Uchiyama (with Shohaku Okumura, Taigen Daniel Leighton)