Life - Stand Guard at the Door of your Mind

Coming empty-handed, going empty-handed -- that is human.
When you are born, where do you come from?
When you die, where do you go?
Life is like a floating cloud which appears.
Death is like a floating cloud which disappears.
The floating cloud itself originally does not exist.
Life and death, coming and going, are also like that.
But there is one thing which always remains clear.
It is pure and clear, not depending on life and death.

Then what is the one pure and clear thing?