This article examines the patronage landowning magnates and noblemen exercised over their parishes in the light of 17th-18th century sources on noble families of the Voivodship of Sandomierz. The patronage was of course conditioned by the landlord's title to the land. The author suggests some ways of examining the sources (donations, wills, parcelling out of landed estates) to find out the noblemen's foundations for the benefit of the Church. This article focuses on the activities of that kind performed in the course of 17th century by one the wealthy noble families of that region, the Oleśnickis o f the Arms of Dębno, patrons of the parish churches of Lipsko, Tarłów and Lasocin. It should be noted that family archives usually contain documents concerned with the material aspects of the functioning of the parishes. Those documents have been carefully classified into inventories, compositions, receipts of tithes and rents, acts of lawsuits and assessed for their information value. The records reveal a high number of court actions involving the nobility and the local clergy over tithes, rents, land seizures or unlawful use of land. There is also ample evidence of concord and cooperation between manor and parish. As the material examined in this article indicates the archives of noble families can be an important complement to the typical ecclesiastical sources in studies of the history of Catholic parishes in the Early Modem period. The appendix contains two sources, which belong to the class of inventories and are rather exceptional in the family archives.