In The Legatus Mystery by Rosemary Rowe, the chief priest of Jupiter in the Roman colonia of Glevum, an elderly eccentric, aspires to the post of flamen dialis, chief priest of Jupiter of Rome, the most distinguished of the priesthoods after the pontifex maximus. In fact, he practices already at being so by observing all the rituals and restrictions of that position and requires his young wife to do the same as flaminica dialis.
Here is Cicero outlining these rules:
A great many ceremonies are imposed upon the Flamen Dialis [the priest of Jupiter], and also many restraints, about which we read in the books On The Public Priesthoods and also in Book I of Fabius Pictor's work. Among them I recall the following: 1) It is forbidden the Flamen Dialis to ride a horse; 2) It is likewise forbidden him to view the classes arrayed outside the pomerium [the sacred boundary of Rome], i.e., armed and in battle order---hence only rarely is the Flamen Dialis made a Consul, since the conduct of wars is entrusted to the Consuls; 3) It is likewise forbidden for him ever to take an oath by Jupiter; 4) It is likewise forbidden for him to wear a ring, unless it is cut through and empty; 5) It is also forbidden to carry out fire from the flaminia, i.e., the Flamen Dialis’ house, except for a sacral purpose; 6) if a prisoner in chains enters the house he must be released and the chains must be carried up through the opening in the roof above the atrium or living room onto the roof tiles and dropped down from there into the street;