Internal forum

In the canon law of the Catholic Church, a distinction is made between the internal forum, where an act of governance is made without publicity, and the external forum, where the act is public and verifiable. In canon law, internal forum, the realm of conscience, is contrasted with the external or outward forum; thus, a marriage might be null and void in the internal forum, but binding outwardly, i.e.,in the external forum, for want of judicial proof to the contrary.

That the Church of Christ has judicial and coercive power is plain from the constitution given to it by its Divine Founder (see ecclesiastical courts). This judicial jurisdiction is expressed by the word Forum, the Latin designation for a place containing a tribunal of justice. As the Church is a perfect society, she possesses within herself all the powers necessary to direct her members to the end for which she was instituted and she has a correlative right to be obeyed by those subject to her. This right is called jurisdiction, and it is the source of all the Church's action that is not derived from the power of Sacred orders. It is this jurisdiction which is the foundation of ecclesiastical law, both externally and internally binding, and from Apostolic times it has been put into practice by the Church's rulers. The public judicial power of the Church is explicitly mentioned in Holy Scripture (Matt. 28:17), and the exercise of it is also recorded (Acts 15:29). In other words, just as the civil state has the legitimate jurisdiction over its subjects to guide them to the end for which it is instituted, because it is a perfect society, so likewise the Church, being constituted by Christ as a perfect society, possesses within itself all the powers necessary for lawfully and effectively attaining the end for which it was established.

As the power of the Church extends not only to its individual members but also to the whole corporate body, not only to questions concerning the conscience but also to the public actions of its subjects, ecclesiastical jurisdiction is distinguished into that of the internal and external forum. The jurisdiction of the internal forum deals with questions concerning the welfare of individual Christians and with their relation to God. Hence it is called the forum of conscience (Forum conscientiae). It is also denominated the forum of Heaven (forum poli) because it guides the soul on the path to God. The internal forum is subdivided into the sacramental or penitential, which is exercised in the tribunal of penance or at least is connected with it, and the extra penitential forum. Causes concerning the private and secret needs of the faithful can often be expedited outside the sacramental confession. Thus, vows may be dispensed, secret censures may be absolved, occult impediments of matrimony may be dispensed outside of the tribunal of penance. The internal forum deals therefore directly with the spiritual welfare of the individual faithful. It has reference to the corporate body only secondarily, in as much as the good of the whole organization is promoted by that of the individual members. Owing to the nature of the civil state and the end for which it was instituted, it has no jurisdiction corresponding to the ecclesiastical forum of conscience. Finally, it may so chance that circumstances may bring about a conflict between the internal and external forum. Thus, for example, a marriage may be null and void in the forum of conscience, but binding in the external forum for want of judicial proofs to the contrary, and vice versa.

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