The nun had been teaching at a school in the town of Kysucke Nove Mesto in northern Slovakia when she told unsuspecting pupil Adam Celko, 7, to come to the front of the class.
She then took a needle out of her handbag and rammed it into the boy’s hand in front of the horrified class, telling him that this was how Jesus suffered - and he would too if he behaved badly.
The boy’s outraged mum Helena, 30, said: "When Adam got home he had a wound on the back of his hand and when I asked him what had happened he told me the nun had done it.
"I was completely shocked. I mean, what on earth was she thinking?
Local priest Peter Holbicka said: "The Sister in question has been removed from the school and I shall be taking the matter up with her personally."