We, who are calmer, may conceive the old man to have taken his will to church with him on the morning of his death, he being then greatly troubled about the changes he had in view.

Perhaps he laid the folded parchment on the shelf and rested one of the large books in front of it.

He breathed his last.

Then the old woman, whose duty it was to put the pews in order, hurriedly throwing the books into the cupboard as soon as the dead man was removed, perchance pushed the document so far back that it slipped through the gap and down behind the buffets.
At all events, no one has ever hit upon a likelier explanation..