Both will be canonized -- made saints of the Catholic Church -- after the pope signed decrees of miracles.
The decrees indicate that Pope Paul VI and Moreno performed miracles, as defined by the church, in their lifetimes.
Moreno was the archbishop of El Salvador and denounced the repression of the country's civil war between 1980 and 1982. When the U.S.-backed Salvadorian army was found to use death squads and torture in its fight against leftist groups seeking power, Moreno spoke out against the government's actions.
In his final homily in 1980, Moreno said, "The law of God which says thou shalt not kill must come before any human order to kill. It is high time you recovered your conscience. I implore you, I beg you, I order you in the name of God: Stop the repression."
The following day, Moreno was shot to death by a sniper while celebrating a Catholic Mass in a hospital chapel. No one was prosecuted for the killing, and Moreno remains an honored figure in El Salvador.
Pope Paul VI brought sweeping changes to the Catholic Church during his tenure from 1963 to 1978. While he maintained the church's opposition to birth control in a 1968 encyclical, he liberalized the church and permitted Mass to be celebrated in languages other than Latin.
Both Moreno and Paul VI will be honored in sainthood ceremonies later this year.