The institutio auctorisabilis is nothing but an approbation required for the validity of acts of jurisdiction, granted by the bishop to a beneficiary in view of his undertaking the care of souls (cura animarum). It is an act of the same nature as the approbation which a bishop gives members of a religious order for hearing confessions of persons not subject to their authority, and without which the absolution would be invalid; but there is this difference that in the case of the institutio auctorisabilis the approbation relates to the exercise of the ministerial functions taken as a whole. It is the missio canonica indispensable for the validity of acts requiring an actual power of jurisdiction. This institution, which is reserved to the bishop or his vicar-general and to those possessing a quasi-episcopal jurisdiction, is required when the institutio tituli collativa belongs to an inferior prelate, a chapter, or a monastery. The institutio tituli collativa given by the bishop himself implies the institutio auctorisabilis, which, therefore, needs not to be given by a special act.
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