Incorruptibility is a belief held by some religious groups, such as Catholics and Orthodox Christians, that God's help can prevent certain human bodies (like those of holy people called saints and beati) from decaying completely or partially after death. This is seen as a sign of their holiness. This belief is said to happen even when conditions that usually cause quick decay are present, as seen in the cases of saints Catherine of Genoa, Julie Billiart, and Francis Xavier.

Catholicism

In Catholicism, if a body is found to be not decayed after death, this is often seen as a sign that the person may be a saint. According to canon law, the body can be examined so that relics can be taken and sent to Rome. The relics must be sealed with wax, and the body must be returned after the inspection. These inspections are rare and can only be done by a bishop as required by canon law. A special church group can approve the inspection and request a written report. After a formal inspection, the body may be placed in an open container for people to honor and respect. Catholic law allows saints to be buried under altars, so Mass can be celebrated above their remains.

Sometimes only part of a body remains uncorrupted. For example, the body of Anthony of Padua was mostly decayed, but his tongue and jaw were preserved. Bonaventure, one of the people who examined the body in 1263, believed this showed Anthony was a "messenger of God's love." A religious story also says the tongue's preservation was due to the "perfection of the teachings formed upon it."

Incorruptibility is different from good preservation or mummification. Incorruptible bodies may have a sweet or floral smell called the "odour of sanctity." Not all saints are expected to have an incorruptible body. Although people may see incorruptibility as a miracle, it is no longer considered a miracle when recognizing a saint.

Bodies that are embalmed are not considered incorruptible. For example, Pope John XXI's body was found to be well-preserved after being exhumed, but Church officials noted it had been embalmed and that his sealed coffin had no oxygen.

The remains of Bernadette Soubirous were checked many times. Church officials confirmed the body was preserved. In 1919, the opening of her coffin was attended by canons, the mayor, and the bishop. This was repeated in 1925. However, her face and hands were covered with a wax mask.

The remains of Teresa of Ávila, held at Alba de Tormes, were examined in 1914 and declared "completely incorrupt," as they had been in 1750 by the Diocese of Ávila. They were checked again in 2024 and found to be in the same condition as in 1914 by the postulator general of the Discalced Carmelite Order.

Eastern Orthodoxy

To the Eastern Orthodox, there is a difference between natural mummification and what is thought to be caused by supernatural forces, called incorruptibility. While incorruptibility is usually not considered necessary for being recognized as a saint, it is said that many Eastern Orthodox saints have been found to have incorrupt bodies. These saints are highly respected. These include:

Judaism

Rabbi Louis Ginzberg, in his important book Legends of the Jews (Vol. 4, Chapter 10), wrote about a story from Jewish texts called the Apocrypha and Aggadah. The story describes a claim that the body of Baruch, a scribe who worked with the prophet Jeremiah (whose tomb is located in Iraq), did not decay. Similar stories are also told about later Hasidic saints, such as Rebbe Elimelech of Lizhensk, Rebbe Sholom Dovber Schneersohn, and others.