Frederick Oakeley

 O Antiphons

 Oates's Plot

 Oaths

 English Post-Reformation Oaths

 Archdiocese of Oaxaca

 Monastery of Obazine

 Obba

 Obedience

 Religious Obedience

 Obedientiaries

 Oblate Sisters of Providence

 Oblates of Mary Immaculate

 Oblates of Saint Francis de Sales

 Oblati

 Obligation

 Tighernach O'Braein

 Obregonians

 Obreption

 Terence Albert O'Brien

 David O'Bruadair

 Edmund Bailey O'Callaghan

 Torlogh O'Carolan

 Occasionalism

 Occasions of Sin

 Thomas Occleve

 Occult Art, Occultism

 Occurrence

 Vicariate Apostolic of Central Oceania

 Daniel O'Connell

 Charles O'Conor (1)

 Charles O'Conor (2)

 Octavarium Romanum

 Octave

 Gelasius O'Cullenan

 Eugene O'Curry

 Daniel O'Daly

 Donogh Mór O'Daly

 Carlo Odescalchi

 O Deus Ego Amo Te

 Cornelius O'Devany

 St. Odilia

 St. Odilo

 John Mary Odin

 Walter Odington

 St. Odo

 St. Odo (Oda)

 Odo

 Edmund O'Donnell

 John O'Donovan

 Bl. Odo of Cambrai

 Odo of Canterbury

 Odo of Cheriton

 Odo of Glanfeuil

 John O'Dugan

 Joseph O'Dwyer

 Johann Œcolampadius

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 John James Maximilian Oertel

 Oettingen

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 Maurice O'Fihely

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 Eugene O'Growney

 John O'Hagan

 Thomas O'Hagan

 John O'Hanlon

 Theodore O'Hara

 Patrick O'Hely

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 Ambrose Bernard O'Higgins

 Ohio

 Aloys Karl Ohler

 Dermod O'Hurley

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 Nicole Oresme

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 Henry Nutcombe Oxenham

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 Antoine-Frédéric Ozanam

 Jacques Ozanam

 Ozias

Omission


(Latin omittere, to lay aside, to pass away).

"Omission" is here taken to be the failure to do something one can and ought to do. If this happens advertently and freely a sin is committed. Moralists took pains formerly to show that the inaction implied in an omission was quite compatible with a breach of the moral law, for it is not merely because a person here and now does nothing that he offends, but because he neglects to act under circumstances in which he can and ought to act. The degree of guilt incurred by an omission is measured like that attaching to sins of commission, by the dignity of the virtue and the magnitude of the precept to which the omission is opposed as well as the amount of deliberation. In general, according to St. Thomas, the sin of omission consisting as it does in a leaving out of good is less grievous than a sin of commission which involves a positive taking up with evil. There are, of course, cases in which on account of the special subject matter and circumstances it may happen that an omission is more heinous. It may be asked at what time one incurs the guilt of a sin of omission in case he fails to do something which he is unable to do, by reason of a cause for which he is entirely responsible. For instance, if a person fails to perform a duty in the morning as a result of becoming inebriated the previous night. The guilt is not incurred at the time the duty should be performed because while intoxicated he is incapable of moral guilt. The answer seems to be that he becomes responsible for the omission when having sufficiently foreseen that his neglect will follow upon his intoxication he does nevertheless surrender himself to his craving for liquor.

RICKABY, Aquinas Ethicus (London, 1896); BOUQUILLON, Theologia moralis fundamentalis (Bruges, 1903); St. Thomas Aquinas, Summa Theologica (Turin, 1885).

JOSEPH F. DELANY