Seal of the Confessional and the Catholic Church

In the Roman Catholic Church, the Seal of Confession (or Seal of the Confessional) is the absolute duty of priests not to disclose anything that they learn from penitents during the course of the Sacrament of Penance.

Gratian, who compiled the edicts of previous Catholic Ecumenical Councils and the principles of church law, published the Decretum about 1151. It includes the following declaration of the law as to the seal of confession: "Let the priest who dares to make known the sins of his penitent be deposed." Gratian goes on to say that the violator of this law should be made a lifelong, ignominious wanderer (Secunda pars, dist. VI, c. II).

Canon 21 of the Fourth Council of the Lateran (1215), binding on the whole church, laid down the obligation of secrecy in the following words:

Let the priest absolutely beware that he does not by word or sign or by any manner whatever in any way betray the sinner: but if he should happen to need wiser counsel let him cautiously seek the same without any mention of person. For whoever shall dare to reveal a sin disclosed to him in the tribunal of penance we decree that he shall be not only deposed from the priestly office but that he shall also be sent into the confinement of a monastery to do perpetual penance

Notably, neither this canon nor the law of the Decretum purports to enact for the first time the secrecy of confession. The 15th century English canonist William Lyndwood speaks of two reasons why a priest is bound to keep secret a confession, the first being on account of the sacrament because it is almost (quasi) of the essence of the sacrament to keep secret the confession. (Cf. also Jos. Mascardus, De probationibus, Frankfort, 1703, arg. 378.)

According to Roman Catholic canon law, "The sacramental seal is inviolable; therefore it is absolutely forbidden for a confessor to betray in any way a penitent in words or in any manner and for any reason." (983 §1) The confessor is always an ordained priest, because in the Catholic Church only ordained priests can absolve sins; lay confession is not recognized. Any lay members who overhear a confession (example: a translator) are likewise bound by the seal. (983§2)

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