John says in the play that Abigail "hopes to dance with me upon my wife's grave."
He happens upon Susan's grave, and goes back home.
"Sixty thousand curses upon your grave, may it be an early one."
I have sworn the oath of blood upon our father's grave.
He was buried and later a strange plant grew upon his grave.
"Upon our father's grave," he proclaimed in a clear, convincing voice, meanwhile raising his right hand.
Fearfully she turned back to look at the tree upon her father's grave.
Bear with me now, while I spit in fancy upon his grave.
Delight dawned upon his grave, considering face and spread wide.