Analysis of The Voice

From our low seat beside the fire
Where we have dozed and dreamed, and watched the glow
Or raked the ashes, stooping so
We scarcely saw the sun and rain
Through the small curtained window-pane,
Or looked much higher
Than this same quiet red or burned-out fire,
Tonight we heard a call,
A voice on the sharp air,
And felt a breath stirring our hair,
A flame within us. Something swift and tall
Swept in and out and that was all.
Was it a bright or a dark angel? Who can know?
It made no mark upon the snow;
But suddenly, in passing, snapped the chain,
Unbarred, flung wide the door
Which will not shut again:
And so we cannot sit here any more.
We must arise and go.
The world is cold without
And dark and hedged about
With mystery and enmity and doubt,
But we must go,
Though yet we do not know  
Who called, or what marks we shall leave upon the snow.