For one who is temperate in food and recreation, who is detached and self-restrained in work, who is regulated in sleep and in vigil—Yoga brings about the cessation of the travail of Samsàra [i.e., the problem of suffering.
Give the organ of taste a free rein, and the other organs will also run on unbridled.
— Swami Vivekananda (CW, 5:414)
Service of the Devas, holy men, teachers, parents and wise persons, as also observance of cleanliness, uprightness, continence and non-injury—these constitute austerities pertaining to the body.
The chaste brain has tremendous energy and gigantic will – power. Without chastity there can be no spiritual strength. Continence gives wonderful control over mankind. The spiritual leaders of men have been very continent, and this is what gave them power.
— Swami Vivekananda (CW, 1:263)
Serenity of mind, gentleness, moderation in speech, self-control, and purity of heart—these are called austerity of the mind.
The purer the mind, the easier it is to control. Purity of the mind must be insisted upon if you would control it.
— Swami Vivekananda (CW, 6.126)
Speaking only words that are inoffensive, true, pleasant and beneficial, as also regular recitation of scriptures, constitute austerity pertaining to speech.
One man calls another a fool, and at this the other stands up and clenches his fist and lands a blow on his nose. Look at the power of the word! … Day and night we manipulate this force without thought and without inquiry. To know the nature of this force and to use it well is also a part of Karma-Yoga [or how to work wisely].
— Swami Vivekananda (CW, 1:74-75)