The Bhagavad Gita by Eknath Easwaran

The Power of Faith ╯
23
Om Tat Sat : these three words represent Brahman,
from which come priests and scriptures and
sacrifice. 24 Those who follow the Vedas, therefore,
always repeat the word Om when offering sacrifices,
performing spiritual disciplines, or giving gifts.
25
Those seeking liberation and not any personal
benefit add the word Tat when performing these
acts of worship, discipline, and charity. 26 Sat
means “that which is”; it also indicates goodness.
Therefore it is used to describe a worthy deed.
27
To be steadfast in self-sacrifice, self-discipline, and
giving is sat . To act in accordance with these three is
sat as well. 28 But to engage in sacrifice, self-discipline,
and giving without good faith is asat, without worth
or goodness, either in this life or in the next.
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