Workers and clerics assisting the dozens of Catholic cardinals set to gather Wednesday to begin voting on the next pope had to swear to never reveal anything about the proceedings or else risk the Church’s gravest punishment: religious banishment. The employees took their oaths in the Papal Chapel.

The Vatican also plans to use signal jamming during the conclave to prevent electronic surveillance or communication outside the conclave, with the Vatican gendarmes overseeing the security measures. The provisions for the oath-taking are laid down in Vatican law.

Cooks and cleaners as well as maintenance and medical staff joined members of the Vatican's clergy on Monday (May 5) to take an oath of secrecy ahead of the upcoming papal conclave. Could cells grow food for astronauts on long missions in space?