A term used here, not in its general meaning, but as a somewhat less than satisfactory translation of the Latin observantia of Catholic moral theologians. It is the proper name of the virtue inclining a man to satisfy his obligation of respect and submission toward those superior to himself in dignity and authority. It is like piety, which disposes one to render the debt of reverence and submission to his parents, except that the persons revered by this virtue are those endowed with an official dignity and authority. A person in a position of authority in the state, for example, shares according to the measure of his office in the excellence and principality of the state itself, and on account of this, respect and, when he commands within the limits of his authority, submission are due to him—respect because of his official position and dignity; submission because of his authority.
Observantia is closely associated with obedience, but differs from it in being concerned more with securing a general attitude of submission, while obedience has for its object the execution of specific commands. It is also associated with the virtue of respect (dulia), differing from it in requiring the tribute of respect for the specific excellence of authority, while dulia pays respect to any excellence or superiority.
As is the case with other moral virtues, failure by way of either defect or excess is possible. Defect consists in the withholding of due respect or submission; excess, in their exaggeration.
Bibliography: thomas aquinas, Summa theologiae 2a2ae, 102.