Arrested cardinal repeatedly warned Holy See of Chinese persecution, condemned Vatican's secretary of state

Zen has repeatedly warned the Vatican of increasing government persecution of religious minorities and anti-communist public figures but has historically received next to no response.

Zen has served as an unofficial spokesman for the underground Catholic community, which has seen little support or protection from the Chinese government. The Chinese Communist Party (CCP) explicitly condemns the underground church for its affiliation and loyalty to a foreign power – the worldwide Catholic communion.

Zen previously dismissed fears that he was a target for arrest, stating that he tries not to provoke them into action. However, in a lucid bit of foresight, Zen acknowledged that "no public person who dares to speak freely can feel safe anymore."