Black Beetles in Amber

"He says that he's instructed to reply
(And he has so instructed me) that sin
Like yours--and this poor gentleman's who's in
For bad advice to you--comes rather high;
But since, apparently, you both begin
To feel some pious promptings to the right,
And fain would turn your faces to the light,
Eternity seems all too long a term.
So 'tis commuted to one-half. I'm quite
Prepared, when that expires, to free the worm
And quench the fire." And, civilly retreating,
He left them holding their protracted meeting.