I'm not exactly sure which passage it is, but in the Bible Jesus get tempted by the devil and he claims we should not tempt our Lord. Who can guarantee that he truly forgives sins, especially the ones we do knowingly (this is a mortal sin bytheway)! Just because the prisoners repent, it doesn't mean God automatically forgives them anyway. Who knows if Purgatory is all about making up for past sins, even the ones you were forgiven for?
Quest