Torture: Cleansing of the Soul
 

"It was often believed, in Catholic countries, that the soul of a heretic or witch was corrupted, filthy, and bedevilled by all manner
of foulness. To cleanse them before punishment, sometimes the victims were forced to consume heated or scalding
consumables (scalding water, fire brands, coals, even soaps). The modern day 'washing the mouth out with soap' is a direct
descendant."