Reply Obj. 2: Personal tithes are due to the church in whose parish a man dwells, while predial tithes seem more reasonably to belong to the church within whose bounds the land is situated. The law, however, prescribes that in this matter a custom that has obtained for a long time must be observed [*Cap. Cum sint, and Cap. Ad apostolicae, de Decimis, etc.]. The shepherd who grazes his flock at different seasons in two parishes, should pay tithe proportionately to both churches. And since the fruit of the flock is derived from the pasture, the tithe of the flock is due to the church in whose lands the flock grazes, rather than to the church on whose land the fold is situated.
Reply Obj. 3: Just as the Church can hand over to a layman the things she receives under the title of tithe, so too can she allow him to receive tithes that are yet to be paid, the right of receiving being reserved to the ministers of the Church. The motive may be either the need of the Church, as when tithes are due to certain soldiers through being granted to them in fee by the Church, or it may be the succoring of the poor; thus certain tithes have been granted by way of alms to certain lay religious, or to those that have no care of souls. Some religious, however, are competent to receive tithes, because they have care of souls. _______________________
FOURTH ARTICLE [II-II, Q. 87, Art. 4]
Whether the Clergy Also Are Bound to Pay Tithes?
Objection 1: It would seem that clerics also are bound to pay tithes. By common law [*Cap. Cum homines, de Decimis, etc.] the parish church should receive the tithes on the lands which are in its territory. Now it happens sometimes that the clergy have certain lands of their own on the territory of some parish church, or that one church has ecclesiastical property on the territory of another. Therefore it would seem that the clergy are bound to pay predial tithes.
Obj. 2: Further, some religious are clerics; and yet they are bound to pay tithes to churches on account of the lands which they cultivate even with their own hands [*Cap. Ex parte, and Cap. Nuper.]. Therefore it would seem that the clergy are not immune from the payment of tithes.
Obj. 3: Further, in the eighteenth chapter of Numbers (26, 28), it is prescribed not only that the Levites should receive tithes from the people, but also that they should themselves pay tithes to the high-priest. Therefore the clergy are bound to pay tithes to the Sovereign Pontiff, no less than the laity are bound to pay tithes to the clergy.
Obj. 4: Further, tithes should serve not only for the support of the clergy, but also for the assistance of the poor. Therefore, if the clergy are exempt from paying tithes, so too are the poor. Yet the latter is not true. Therefore the former is false.
On the contrary, A decretal of Pope Paschal [*Paschal II] says: "It is a new form of exaction when the clergy demand tithes from the clergy" [*Cap. Novum genus, de Decimis, etc.].
I answer that, The cause of giving cannot be the cause of receiving, as neither can the cause of action be the cause of passion; yet it happens that one and the same person is giver and receiver, even as agent and patient, on account of different causes and from different points of view. Now tithes are due to the clergy as being ministers of the altar and sowers of spiritual things among the people. Wherefore those members of the clergy as such, i.e. as having ecclesiastical property, are not bound to pay tithes; whereas from some other cause through holding property in their own right, either by inheriting it from their kindred, or by purchase, or in any other similar manner, they are bound to the payment of tithes.