Lines from R.S. Thomas' poem "The Belfry"

The poem by R.S. Thomas ends with the possibility of faraway hope, but some days, today for example, I can't get past these lines:

 
                 There are times
When a black frost is upon
One's whole being, and the heart
In its bone belfry hangs and is dumb. 
     - from "The Belfry" by R.S. Thomas 

       (More from R.S. Thomas)