From the "Orphica"

And you shall find, arrived in Hades' land,
A spring and a white cypress there beside;
But come not near; on these banks do not stand;
For from the pool of Memory a tide

Of water, cool and rapid, pouring forth,
And by Her pool a gaurdian: this thy
Password: "A child I am of heaven and earth;
Yea, even thus. My birth was of the sky.

But I am dry with thirst and perishing.
Give me to drink from the pool of memory.
And this allowed, to taste the holy spring,
With heroes dwell, a god new born in thee.

-Translated from the Greek by Thomas Banks-