Source: http://www.vatican.va/archive/ENG1104/__P3S.HTM
Timestamp: 2019-04-20 00:32:10+00:00

Document:
Can. 1040 Those aVected by any impediment, whether perpetual, which is called an irregularity, or simple, are prevented from receiving orders. The only impediments incurred, however, are those contained in the following canons.
6/ a person who has placed an act of orders reserved to those in the order of episcopate or presbyterate while either lacking that order or prohibited from its exercise by some declared or imposed canonical penalty.
3/ a neophyte unless he has been proven sufficiently in the judgment of the ordinary.
Can. 1043 If the Christian faithful are aware of impediments to sacred orders, they are obliged to reveal them to the ordinary or pastor before the ordination.
3/ a person who has committed a delict mentioned in ⇒ can. 1041, nn. 3, 4, 5, 6.
2/ a person who is aVected by amentia or some other psychic illness mentioned in ⇒ can. 1041, n. 1 until the ordinary, after consulting an expert, permits the exercise of the order.
Can. 1045 Ignorance of the irregularities and impediments does not exempt from them.
Can. 1046 Irregularities and impediments are multiplied if they arise from different causes. They are not multiplied, however, if they arise from the repetition of the same cause unless it is a question of the irregularity for voluntary homicide or for having procured a completed abortion.
Can. 1047 §1. Dispensation from all irregularities is reserved to the Apostolic See alone if the fact on which they are based has been brought to the judicial forum.
3/ the impediment mentioned in ⇒ can. 1042, n. 1.
§3. Dispensation in public cases from the irregularities from exercising an order received mentioned in ⇒ can. 1041, n. 3, and even in occult cases from the irregularities mentioned in ⇒ can. 1041, n. 4 is also reserved to the Apostolic See.
§4. An ordinary is able to dispense from irregularities and impediments not reserved to the Holy See.
Can. 1048 In more urgent occult cases, if the ordinary or, when it concerns the irregularities mentioned in ⇒ can. 1041, nn. 3 and 4, the Penitentiary cannot be approached and if there is imminent danger of grave harm or infamy, a person impeded by an irregularity from exercising an order can exercise it, but without prejudice to the obligation which remains of making recourse as soon as possible to the ordinary or the Penitentiary, omitting the name and through a confessor.
Can. 1049 §1. Petitions to obtain a dispensation from irregularities or impediments must indicate all the irregularities and impediments. Nevertheless, a general dispensation is valid even for those omitted in good faith, except for the irregularities mentioned in ⇒ can. 1041, n. 4, and for others brought to the judicial forum, but not for those omitted in bad faith.
§2. If it is a question of the irregularity from voluntary homicide or a procured abortion, the number of the delicts also must be mentioned for the validity of the dispensation.
§3. A general dispensation from irregularities and impediments to receive orders is valid for all the orders.

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