Code_of_Canon_Law

Can. 17 Ecclesiastical laws are to be understood according to the proper meaning of the words
considered in their text and context. If the meaning remains doubtful or obscure, there must be
recourse to parallel places, if there be any, to the purpose and circumstances of the law, and to
the mind of the legislator.
Can. 18 Laws which prescribe a penalty, or restrict the free exercise of rights, or contain an
exception to the law, are to be interpreted strictly.
Can. 19 If on a particular matter there is not an express provision of either universal or particular
law, nor a custom, then, provided it is not a penal matter, the question is to be decided by taking
into account laws enacted in similar matters, the general principles of law observed with
canonical equity, the jurisprudence and practice of the Roman Curia, and the common and
constant opinion of learned authors.
Can. 20 A later law abrogates or derogates from an earlier law, if it expressly so states, or if it is
directly contrary to that law, or if it integrally reorders the whole subject matter of the earlier
law. A universal law, however, does not derogate from a particular or from a special law, unless
the law expressly provides otherwise.
Can. 21 In doubt, the revocation of a previous law is not presumed; rather, later laws are to be
related to earlier ones and, as far as possible, harmonised with them.
Can. 22 When the law of the Church remits some issue to the civil law, the latter is to be
observed with the same effects in canon law, insofar as it is not contrary to divine law, and
provided it is not otherwise stipulated in canon law.
TITLE II: CUSTOM
Can. 23 A custom introduced by a community of the faithful has the force of law only if it has
been approved by the legislator, in accordance with the following canons.
Can. 24 §1 No custom which is contrary to divine law can acquire the force of law.
§2 A custom which is contrary to or apart from canon law, cannot acquire the force of law unless
it is reasonable; a custom which is expressly reprobated in the law is not reasonable.
Can. 25 No custom acquires the force of law unless it has been observed, with the intention of
introducing a law, by a community capable at least of receiving a law.
Can. 26 Unless it has been specifically approved by the competent legislator, a custom which is
contrary to the canon law currently in force, or is apart from the canon law, acquires the force of
law only when it has been lawfully observed for a period of thirty continuous and complete
years. Only a centennial or immemorial custom can prevail over a canonical law which carries a
clause forbidding future customs.
Can. 27 Custom is the best interpreter of laws.