Death, Shadow and Spirit

Death does say to Shadow:

Heaven and earth be not of my work,
and streams do not slow down for me.
But trees wither in my hand,
and deaden as far as I can see.
Humans are masters so they say.
But even I must practice my law,
for I wrinkle their body and make them cold,
making their fingures tender and raw.
They come to this world to live their lives,
however short that might be.
Then I snatch them from their home
because now they belong to me.
I weaken the hearts of those he knew,
their tears flow from their eyes.
To one question they ask over and over,
the simple question, Why?

Shadow replies:

O' high and mighty death,
you do sit so high in your place.
But listen carefully to my words
I will strike anger on thy face.
I am the twin of man,
I follow behind in the day.
I am the darkness that sweeps the night,
to man I have nothing to say.
I hang over man to depress him so,
or fill his hart with hate.
You take the life from them true,
Me?
I must not wait.
For I place the fear upon their faces,
I can create their worst nightmare.
I can haunt them forever in life,
and to death, few men care.

Spirit, who had sat quietly by, in a low voice grumbles:

Though you two be equal in hate,
I control once you are through.
I send them to heaven, or hell if you will,
to paradise I may send you.
I control the substance of things,
and the life given to this land.
I can turn a mountain to dust,
or a rocky peak to sand.
A Spirit is of the elements
which can destroy all eyes can see.
Death, shadow, and man alike,
Though do not wish to cross me...