Pope Francis on Tuesday expanded the criteria for becoming a saint to include “the free offering of one’s life” in an apostolic letter published by the Vatican.

An example of such self-sacrifice could be caring for patients with highly infectious diseases.

Previously, people could be named saints in two ways: if they had been martyred for their Christian faith, or had led a particularly holy life and had miracles credited to them.

Vatican media, however, explained that the new category of sainthood has five stipulations.

In addition to the free and voluntary offering of one’s life, and heroic acceptance of a certain and “soon-to-come death, there must be a close relation “between the offering of one’s life and the premature death of the one who offers it.”

The saintly candidate must have chosen to lead a good Christian life until their death and must have had “the reputation for holiness” before and after dying.

Finally, there must be evidence of a posthumous miracle that could be directly linked to the candidate.

Report says the new category of self-sacrifice does not have to include persecution by non-Christians.