>> Pāḷi vocabulary

= concern, scruple, moral qualm, misgivings, compunction, fear of wrong doing, shrinking back form doing wrong.

Often contrasted to and combined with hirī, both of which it is said at AN 2.9 that they protect the world (lokaṃ pālenti).

Their role as well as their difference can be easily understood thanks to the apt simile of the fortress given at AN 7.67: ottappa is compared to the rampart, that ought to be high and wide, and which prevents the army of Māra from entering the fortress of the mind, whereas hirī is compared to the moat, that ought to be deep and wide. Thus, just as the army has to cross the moat before attacking the rampart, the arising akusala dhammas meet first with hirī, and in the case where it has not been deep and wide enough to ward them off, they subsequently meet with ottappa.

The formula defining what means being ottappī (endowed with ottappa) is found at MN 53, as well as in several suttas of the Aṅguttara Nikāya, and is as follows:

It is easily understood that ottappa, together with hirī, play he key role in the protection of sīla. It also has a deep connexion with sammā-diṭṭhi, since it consists in a yathā·bhūtaṃ understanding of dukkha-samudaya, by seeing from its very beginning the process through which dukkha will arise in the future as a result of failing to prevent the invasion of the mind by the particular akusala dhamma which is arising at the present moment. Thus, the instruction given by the Buddha in the Sīlasampatti Formula: aṇumattesu vajjesu bhaya-dassāvī (seeing danger in the slightest fault [in regards of the Pātimokkha rules]) can be understood as a paraphrase for ottappa.

Ottappa, due to its connexion with sīla, plays also an important role in the Vinaya, and the rules seem to be designed to foster its establishment in the bhikkhus who have proven to have it weak by committing an offense. The most gentle of these measures, in the case of light offenses, is the confession, and the strongest, in the case of a saṅghādisesa offense, is a whole set of humiliating penances, the perspective of which helps to make the utility of ottappa more evident to the potential offender.

These penances include the fact that during at least six days, every day the offender must inform all the bhikkhus in the monastery of the fact that he is observing penance and the precise offense for which the penance was imposed. If visiting bhikkhus come to the monastery, he must inform them as well; if he goes to another monastery, he must inform all the bhikkhus there, too. If, on any day of his penance, the bhikkhu neglects to observe this rule, that day does not count toward the total of six.