Horeb's Shadow

You put away the sheep, secured for night in their fold,
beneath a sky whose blue had long since drained
from its eastern edge.  Its last reserve of light 
illumined your steps.  The cooling air blessed your skin.  
Your tiredness found answer in the darkness of your tent.

At a time like this, it was easy not to think - 
of childhood dreams dreamt long ago,
of a young man's ambition for a life of high calling, 
of bitter failure and the road that led
from there to this desert -
memories dissolved in the clear glass
of thousands of twilights just like this one.

And so you lay down to sleep,
a tree whose time for fruit had passed,
unaware that tomorrow, a bush would burn.

Clarence Thompson's Questions:

1. Does the imagery work in bringing the reader into the scene?

2. Is the subject of the poem clear?

3. In the second stanza, I considered changing "...of bitter failure and the road that led from there to this desert" to, "of bitter failure and the road from there to this desert".  Would this have been better, or would it have been too abrupt?

Thanks!