Who you are, "before your mother and father were even born" as
Huineng said.
Dogen zenji has a verse about this:
Original Face (Honrai no Memmuku)
Spring, cherry blossoms.
In summer, the cuckoo’s song.
The bright moon in autumn and
in winter, snow,
cold, clear.
translated by
Yasuda Joshu Dainen and Anzan Hoshin