The Apostolic constitution Divinus Perfectionis Magister of Pope John Paul II of 25 January 1983 and the norms issued by the Congregation for the Causes of Saints on 7 February 1983 to implement the constitution in dioceses, continued the simplification of the process initiated by Pope Saint Paul VI. Contrary to popular belief, the reforms did not eliminate the office of the Promoter of the Faith (Latin: Promotor Fidei), popularly known as the "Devil's Advocate", whose office is to question the material presented in favor of canonization. The reforms were intended to reduce the adversarial nature of the process. In November 2012 Pope Benedict XVI appointed Monsignor Carmello Pellegrino as Promoter of the Faith.
Canonization is a statement of the Church that the person certainly enjoys the Beatific Vision of Heaven. The title of "Saint" (Latin: "Sanctus" or "Sancta") is then proper, reflecting that the Saint is a refulgence of the holiness of God Himself, which alone comes from God's gift. The Saint is assigned a feast day which may be celebrated anywhere in the universal Church, although it is not necessarily added to the General Roman Calendar or local calendars as an "obligatory" feast; parish churches may be erected in their honour; and the faithful may freely celebrate and honour the Saint.
Although recognition of sainthood by the Pope does not directly concern a fact of Divine revelation, nonetheless it must be "definitively held" by the faithful as infallible pursuant to, at the least, the Universal Magisterium of the Church, because it is a truth related to revelation by historical necessity.
Regarding the Eastern Catholic Churches, individual sui juris churches have the right to "glorify" saints for their own jurisdictions, though this has rarely happened.
Candidates for canonization undergo the following process:
"Servant of God"
The process of canonization commences at the diocesan level. A bishop with jurisdiction, usually the bishop of the place where the candidate died or is buried, although another ordinary can be given this authority, gives permission to open an investigation into the virtues of the individual in response to a petition of members of the faithful, either actually or pro forma. This investigation usually commences no sooner than five years after the death of the person being investigated. The Pope, Bishop of Rome, may also open a process and has the authority to waive the waiting period of five years, e. g., as was done for St. Teresa of Calcutta by Pope John Paul II, and for Lúcia Santos and for Pope John Paul II himself by Pope Benedict XVI. Normally, an association to promote the cause of the candidate is instituted, an exhaustive search of the candidate's writings, speeches, and sermons is undertaken, a detailed biography is written, and eyewitness accounts are collected. When sufficient evidence has been collected, the local bishop presents the investigation of the candidate, who is titled "Servant of God" (Latin: "Servus Dei"), to the Congregation for the Causes of the Saints of the Roman Curia, where the cause is assigned a postulator, whose office is to collect further evidence of the life of the Servant of God. Religious orders that regularly deal with the Congregation often designate their own Postulator General. At some time, permission is then granted for the body of the Servant of God to be exhumed and examined. A certification "non cultus" is made that no superstitious or heretical worship, or improper cult of the Servant of God or his tomb has emerged, and relics are taken and preserved.
"Heroic in Virtue"
When sufficient evidence has been collected, the Congregation recommends to the Pope that he proclaim the heroic virtue of the Servant of God; that is, that the Servant of God exercised to a heroic degree the theological virtues of faith, hope, and charity and the cardinal virtues of prudence, justice, fortitude, and temperance. From this time the one said to be "heroic in virtue" is entitled "Venerable" . A Venerable does not yet have a feast day, permission to erect churches in his honor has not yet been granted, and the Church does not yet issue a statement on his probable or certain presence in Heaven, but prayer cards and other materials may be printed to encourage the faithful to pray for a miracle wrought by his intercession as a sign of God's will that the person be canonized.
Beatification is a statement of the Church that it is "worthy of belief" that the Venerable is in Heaven and saved. Attaining this grade depends on whether the Venerable is a martyr:
For a martyr, the Pope has only to make a declaration of martyrdom, which is a certification that the Venerable gave his life voluntarily as a witness of the Faith or in an act of heroic charity for others.
For a non-martyr, all of them being denominated "confessors" because they "confessed", i. e., bore witness to the Faith by how they lived, proof is required of the occurrence of a miracle through the intercession of the Venerable; that is, that God granted a sign that the person is enjoying the Beatific Vision by performing a miracle for which the Venerable interceded. Presently, these miracles are almost always miraculous cures of infirmity, because these are the easiest to judge given the Church's evidentiary requirements for miracles; e. g., a patient was sick with an illness for which no cure was known; prayers were directed to the Venerable; the patient was cured; the cure was spontaneous, instantaneous, complete, and enduring; and physicians cannot discover any natural explanation therefor.
The satisfaction of the applicable conditions permits beatification, which then bestows on the Venerable the title of "Blessed". A feast day will be designated, but its observance is ordinarily only permitted for the Blessed's home diocese, to specific locations associated with him, or to the churches or houses of the Blessed's religious order if he belonged to one. Parishes may not normally be named in honor of blessed.
To be canonized as a saint, ordinarily at least two miracles must have been performed through the intercession of the Blessed after his death, but for beati confessors, i. e., beati who were not declared martyrs, only one miracle is required, ordinarily being additional to that upon which beatification was premised. Very rarely, a pope may waive the requirement for a second miracle after beatification if he, the Sacred College of Cardinals, and the Congregation for the Causes of Saints all agree that the Blessed lived a life of great merit proven by certain actions. This extraordinary procedure was used in Pope Francis' canonization of Pope John XXIII, who convoked the first part of the Second Vatican Council.