I'll let you ponder on this for a bit...

"With permission of the priest, the family of an incurable sufferer might drop of large stone on his head."

I wonder what was 'classified' as a large stone.... did the church have 'large' stones ready for use on such an occasion? I'd hate to be the first person to be an incurable sufferer, while people drop 'large stones' until they find one big enough to take me down.

The wonder of some medieval church practices... If it were true, yeah I could cite the website, which doesn't provide a cite of itself, but just image for a second it was true, oh how funny it would be... how funny it would be.