"Walking"

...

I am walking,

Though I know not where

My destination rests in waiting,

Nor from what place I am hailing;

I know not whether I will return

Or stay.

...

I am walking,

Alone against an empty night,

Endless as the empty sky

I see all around, in many shades of black,

All the same.

...

I am walking,

And all I hear are echoes,

Calling, calling, and fading,

Unable to resound against the night

Because everything is too distant

To hear.

...

And I think of many things,

Of tomorrows or yesterdays,

Or what was, or is, or could have been;

And I think how trite this thinking seems

Against the world

Of melancholy people.

...

No one transcends the bracing night,

And all is distance absolute,

And I puzzle how long I wish to stay,

Or if I may

Ever leave.

...

"Tomorrow and tomorrow and tomorrow

Creeps in this petty pace,

And all our yesterdays have lighted fools

The way to dusty death..." I muse,

And wonder where I stand:

Yester-night or tomorrow morning.

...

I am walking somewhere, sometime,

And the mist is rising as I lose myself

In the cryptic, lonely folds of this distance absolute;

I think, and muse, and wonder too,

Where am I, where are they, and where are you.

...


That quote is from Shakespeare's Macbeth:

Macbeth:
To-morrow, and to-morrow, and to-morrow,
Creeps in this petty pace from day to day,
To the last syllable of recorded time;
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.

Macbeth Act 5, Scene 5, 19-28