As they had thus an especial supervision of all religious observances, it was to them in case of need--on occasion of marriage, testament, and -adrogatio- -- that the preliminary question was addressed, whether the business proposed did not in any respect offend against divine law; and it was they who fixed and promulgated the general exoteric precepts of ritual, which were known under the name of the "royal laws." Thus they acquired (although not probably to the full extent till after the abolition of the monarchy) the general oversight of Roman worship and of whatever was connected with it--and what was there that was not so connected?
They themselves described the sum of their knowledge as "the science of things divine and human." In fact the rudiments of spiritual and temporal jurisprudence as well as of historical recording proceeded from this college.

For all writing of history was associated with the calendar and the book of annals; and, as from the organization of the Roman courts of law no tradition could originate in these courts themselves, it was necessary that the knowledge of legal principles and procedure should be traditionally preserved in the college of the Pontifices, which alone was competent to give an opinion respecting court-days and questions of religious law.
Fetiales By the side of these two oldest and most eminent corporations of men versed in spiritual lore may be to some extent ranked the college of the twenty state-heralds (-fetiales-, of uncertain derivation), destined as a living repository to preserve traditionally the remembrance of the treaties concluded with neighbouring communities, to pronounce an authoritative opinion on alleged infractions of treaty-rights, and in case of need to attempt reconciliation or declare war.

They had precisely the same position with reference to international, as the Pontifices had with reference to religious, law; and were therefore, like the latter, entitled to point out the law, although not to administer it.
But in however high repute these colleges were, and important and comprehensive as were the functions assigned to them, it was never forgotten--least of all in the case of those which held the highest position--that their duty was not to command, but to tender skilled advice, not directly to obtain the answer of the gods, but to explain the answer when obtained to the inquirer.

Thus the highest of the priests was not merely inferior in rank to the king, but might not even give advice to him unasked.

It was the province of the king to determine whether and when he would take an observation of birds; the "bird-seer" simply stood beside him and interpreted to him, when necessary, the language of the messengers of heaven.
In like manner the Fetialis and the Pontifex could not interfere in matters of international or common law except when those concerned therewith desired it.