What is Zen "practice"?

Green's Sayings of Zen Master Joshu [Zhaozhou]:

181

A monk asked, "What is a person who understands matters perfectly?"

The master said, "Obviously it is great practice."

The monk said, "It's not yet clear to me; do you practice or not?"

The master said, "l wear clothes and eat food."

The monk said, "Wearing clothes and eating food are ordinary things. It's still not clear to me; do you practice or not?"

The master said, "You tell me, what am I doing every day?"

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ewk ^bk note ^txt - Sometimes religious people come in here and make a big deal out of their "practice". What is Zhaozhou's practice? What does he do every day?