Trollope uses “decadence” to suggest not a moral decline, but rather a falling away of affluence in Dillsborough. The death of the old squire affected many of the businessmen in town, especially Mr. Runciman, owner of the local inn, and Mr. Masters, whose family had served the Morton family as attorneys for three generations. In suggesting a decline by using the word “decadence,” Trollope is utilizing a meaning that is found its Latinate components, de, “down,” and cadere, “to fall away.” [CD 2012]
Rector means in Latin “one who corrects or guides.” Mr. Mainwaring is rector not only in the English ecclesiastical sense of the word, but also a rector in the literal Latin sense in that he guides and corrects his curate Mr. Surtees in order to prevent him from overly zealous ecclesiastical work. [CD 2012]
Quieta non movere
From the legal phrase stare decisis et non quieta movere–“to stand by things decided and not to disturb what is settled,” which asserts a court’s deference to previous judicial decisions. Trollope humorously attributes this motto to Mr. Mainwaring, rector of Dillsborough, because of his diligence in making sure the curate, Mr. Surtees, hired for a small portion of the rector’s salary, completes his agreed upon duties yet does not “drive him into activity” through eagerness and innovation. [CD 2012]
Source: Garner, B. A. and H. C. Black. Black’s Law Dictionary. 8th edition. St. Paul: West Group, 2004.