Despite his bad health, Korec continued to work as a street cleaner and as a factory worker. He meanwhile also continued his active life as a leader of the underground Church. He led spiritual retreats for students and counseled young people, seminarians and priests. His private apartment in Petržalka on Vilova Street 7 became a highly-sought centre of his underground ministry. Many people, laypersons and priests went to him for spiritual advice. Because the publication of Christian literature was proscribed, Korec wrote samizdat books, which were secretly printed and distributed. He also secretly ordained priests because the law allowed for the ordination by government-approved clerics and limited ordinations so that it could restrict church activity.