what does the quote and i conceive, moreover, that the hearts holding such miserable secrets as you speak of will yield them up at that last day, not with reluctance, but with joy unutterable mean
My interpretation is this: Those with a guilty conscience will confess their sins on judgment day. Not reluctantly, but willingly, eager to get the weight of their sins off their shoulders.
Answered by
MHood2
That those who carry dark secrets and hidden sins throughout their days will be very willing to unburden themselves when they are at the end of their life. The joy of letting the secrets go will be uplifting. She is also making the point that those who carry around hidden guilt live in a type of personal hell until they do unburden themselves.