Source: http://www.vatican.va/archive/ENG1104/_P3Q.HTM
Timestamp: 2019-04-23 17:58:56+00:00

Document:
Can. 1026 A person must possess due freedom in order to be ordained. It is absolutely forbidden to force anyone in any way or for any reason to receive orders or to deter one who is canonically suitable from receiving them.
Can. 1027 Those aspiring to the diaconate and presbyterate are to be formed by careful preparation, according to the norm of law.
Can. 1028 The diocesan bishop or the competent superior is to take care that before candidates are promoted to any order, they are instructed properly about those things which belong to the order and its obligations.
Can. 1029 Only those are to be promoted to orders who, in the prudent judgment of their own bishop or of the competent major superior, all things considered, have integral faith, are moved by the right intention, have the requisite knowledge, possess a good reputation, and are endowed with integral morals and proven virtues and the other physical and psychic qualities in keeping with the order to be received.
Can. 1030 Only for a canonical cause, even if occult, can the proper bishop or competent major superior forbid admission to the presbyterate to deacons subject to him who are destined to the presbyterate, without prejudice to recourse according to the norm of law.
Can. 1031 §1. The presbyterate is not to be conferred except on those who have completed the twenty-fifth year of age and possess sufficient maturity; an interval of at least six months is to be observed between the diaconate and the presbyterate. Those destined to the presbyterate are to be admitted to the order of deacon only after completing the twenty-third year of age.
§2. A candidate for the permanent diaconate who is not married is not to be admitted to the diaconate until after completing at least the twenty-fifth year of age; one who is married, not until after completing at least the thirty-fifth year of age and with the consent of his wife.
§3. The conference of bishops is free to establish norms which require an older age for the presbyterate and the permanent diaconate.
§4. A dispensation of more than a year from the age required according to the norm of §§1 and 2 is reserved to the Apostolic See.
Can. 1032 §1. Those aspiring to the presbyterate can be promoted to the diaconate only after they have completed the fifth year of the curriculum of philosophical and theological studies.
§2. After a deacon has completed the curriculum of studies and before he is promoted to the presbyterate, he is to take part in pastoral care, exercising the diaconal order, for a suitable time defined by the bishop or competent major superior.
§3. A person aspiring to the permanent diaconate is not to be promoted to this order unless he has completed the time of formation.

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