Answered by Father Jeremiah Payne, St. Joseph Catholic Parish, Palm Bay, May 19, 2017.
Asked by Thomas, a 5th grade student at Sacred Heart Catholic School, New Smyrna.
Canonization is the formal process by which someone is recognized to be a saint, namely one already in Heaven, and who is a worthy example of the Christian life and allowed to be recognized at the Altar as such a witness.
In the earliest days of the Church, this recognition was often granted after a long period of everyone agreeing the person was a saint. In modern days, the process is very formal. The first step usually begins at the local level where a “cause” for a particular person is begun. The person is investigated to see if they possessed extraordinary virtue in their earthly life. If this is found to be the case, the person receives the title Servant of God (Servus Dei) and the case is forwarded to the Vatican Congregation for the Causes of Saints, where a more formal investigation starts.
When the Congregation fully investigates the person and finds them to be a person of “heroic virtue”, they are presented to the Pope for the title of Venerable (Venerabilis). At this point, holy cards and other items of devotion may be made so as to ask the Venerable for a miracle. There are two miracles needed to complete the process to prove that the Venerable is in Heaven interceding before the throne of God.
The next step is for there to be a declaration that the person is Blessed (Beatus), meaning that the Pope declares it “worthy of belief” that the person is in Heaven. If the person is a martyr (meaning he died for his faith), the Pope can declare this directly and immediately. If the person is not a martyr, then a miracle happening only because of the Venerable must be proved. Usually it is a medical miracle that is spontaneous (unplanned), instantaneous (happen right away), complete and lasting; and teams of physicians and scientists cannot find any natural reason for it to have happened (this team is made up of Catholics and non-Catholics, believers and non-believers alike). If a person is declared “Blessed”, she or he may be venerated (honored or recognized) in her or his home place and other places related to him or her.
The final step is canonization, the statement that a person is a saint (Sanctus). For a person who is not a martyr, there is the requirement of another verified miracle. Once that happens and is proven, the Pope declares that the person is indeed enjoying the Beatific Vision of God in Heaven and can, therefore, be venerated in all places and added to the General Calendar of the Roman Catholic Church.