Ecclesiastical jurisdiction is jurisdiction by church leaders over other church leaders and over the laity.

Jurisdiction is a word borrowed from the legal system which has acquired a wide extension in theology, wherein, for example, it is frequently used in contradistinction to order, to express the right to administer sacraments as something added onto the power to celebrate them. So it is used to express the territorial or other limits of ecclesiastical, executive or legislative authority. Here it is used as the authority by which judicial officers investigate and decide cases under canon law.

Such authority, in the minds of lay Roman lawyers who first used the word "jurisdiction", was essentially temporal in its origin and in its sphere. Christians transferred the notion to the spiritual domain as part of the general idea of a Kingdom of God focusing on the spiritual side of man upon earth.

It was viewed as also ordained of God, who had dominion over his temporal estate. As the Church in the earliest ages had executive and legislative power in its own spiritual sphere, so also it had judicial officers, investigating and deciding cases. Before its union with the State, its power in this direction, as in others, was merely over the spirits of men. Coercive temporal authority over their bodies or estates could only be given by concession from the temporal ruler. Moreover, even spiritual authority over members of the Church, i.e. baptized persons, could not be exclusively claimed as a right by the Church tribunals, if the subject matter of the cause were purely temporal. On the other hand, it is clear that all the faithful were subject to these courts (when acting within their own sphere), and that, in the earliest times, no distinction was made in this respect between clergy and laity.

The Catholic Church claims to be the Church founded by Jesus Christ for the salvation of men. The Catholic Church needs a regulating power (the authority of the Church). The decree Lamentabili sane, of 3 July 1907, rejects the doctrine that Christ did not desire to found a permanent, unchangeable Church endowed with authority.

It is customary to speak of a threefold office of the Church: the office of teaching (prophetic office), the priestly office and the pastoral office (governing office). To those are attached the threefold authority of the Church: the teaching authority, ministerial authority and ruling authority. Since the teaching of the Church is authoritative, the teaching authority is traditionally included in the ruling authority; then only the ministerial authority and the ruling authority are distinguished.

By ministerial authority, which is conferred by an act of consecration, is meant the inward, and because of its indelible character permanent, capacity to perform acts by which Divine grace is transmitted. By ruling authority, which is conferred by the Church (missio canonica, canonical mission), is understood the authority to guide and rule the Church of God. Jurisdiction, insofar as it covers the relations of man to God, is called jurisdiction of the internal forum or jurisdiction of the forum of Heaven (jurisdictio poli) (see Ecclesiastical Forum); this again is either a) sacramental or penitential, so far as it is used in the Sacrament of Penance, or b) extra-sacramental, e.g. in granting dispensations from private vows. Jurisdiction, insofar as it regulates external ecclesiastical relations, is called jurisdiction of the external forum, or briefly jurisdictio fori. This jurisdiction, the actual power of ruling is legislative, judicial or coactive. Jurisdiction can be possessed in varying degrees. It can also be held either for both fora, or for the internal forum only, e.g. by the parish priest.

Jurisdiction can be further sub-divided into ordinary, quasi-ordinary and delegated jurisdiction.