“(Fr. Brian Harrison states) ‘While resignationists [i.e. those who hold that Benedict’s resignation was invalid] claim that in canon law munus and ministerium have distinct meanings, they are often in practice used synonymously.’ However, in order that what is juridically intended be intelligibly expressed in a juridical act, the terms used in the document must be understood as they are defined in law, otherwise the juridical intent of the act will not be intelligible, with the consequence that the act will be null and void due to defect of intention. Ecclesiastical laws must be understood according to the proper signification of the terms considered in their text and context749 (Can. 17; [Canon 18 in the 1917 Code]). Canon 332 § 2 decrees that in order to be valid the pope’s renunciation of his munus must be ‘rightly manifested’, which means not only that he must follow the correct procedure, but he must also rightly express his renunciation in accordance with the letter of the law. In order to rightly express his juridical intent he must properly intend that his words be understood as they are defined and understood in law, otherwise they will be ambiguous or even unintelligible. Therefore, in establishing that for the validity of a papal renunciation it is required that the act be rightly manifested, canon 332 § 2 thereby established the necessity for the renunciation to be expressed in a manner that intends the legal terms employed in the act to be understood as those terms are defined in law. If the pope wishes to deviate from this statutory requirement that his act be rightly manifested in accordance with law, he must make a provision for the exception, since an administrative act has no effect to the extent that it is contrary to an approved law or custom, unless the competent authority had expressly added a derogating clause. (Canon 38) 750 This is why so many papal acts and decrees have ended with a clause saying, ‘Notwithstanding anything to the contrary,’ or, ‘Notwithstanding any other provisions of law, even incapacitating or nullifying ones.’ So if in Benedict’s Declaratio the term ministerium was intended to be synonymous with munus, that alone would of itself invalidate the act.”
Kramer, Paul. On the true and the false pope: The case against Bergoglio (pp. 506-507). Gondolin Press. Kindle Edition.