Kena Upanishad

Once upon a time, Spirit planned that the gods might win a great victory.  The gods grew boastful; thou Spirit had planned their victory, they thought they had done it all.Spirit saw their vanity and appeared.  they could not understand; they said: "Who is that mysterious person?"
They said to Fire: "Fire! Find out who is that mysterious person"
Fire ran to Spirit. Spirit asked what it was. Fire said: "I am Fire; known to all!"
Spirit asked: "What can you do?" Fire said: "I can burn anything and everything in this world."
"Burn it" said Spirit, putting a straw on the ground.
Fire threw itself upon the straw, but could not burn it.
Then Fire ran to the gods in a hurry and confessed it could not find out who was that mysterious person.
Then the gods asked Wind to find out who was that mysterious person.
Wind ran to Spirit and Spirit asked what it was. Wind said: "I am Wind; I am the King of the Air."
Spirit asked: "What can you do?"  and Wind said; "I can blow away anything and everything in this world."
"Blow it away" said Spirit, putting a straw on the ground. Wind threw itself upon the straw, but could not move it.  Then Wind ran to the gods in a hurry and confessed it could not find out who was that mysterious person.
Then the gods went to Light and asked it to find out who was that mysterious person.  Light ran towards Spirit, but Spirit disappeared upon the instant.
Then appeared in the sky that pretty girl, the goddess of Wisdom.  Light went to her and asked who was that mysterious person.

The goddess said: "Spirit, through Spirit you attained your greatness. Praise the greatness of Spirit." Then Light knew that the mysterious person was none but Spirit.
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Spirit is the Good in all. It should be worshipped as the Good.  He who knows this shall prevail against evil, enjoy the Kingdom of Heaven, yes, for ever enjoy the blessed Kingdom of Heaven.