Tao Te Ching 8.1

"'Bhishma said, "I shall speak to thee of that by which thou mayst attain to high merit. Possessed as thou art of wisdom, thou shalt be gratified with the knowledge I will impart to thee, like a person gratified with having quaffed nectar. The rules of duty that have been uttered by the great Rishis, each relying upon his own wisdom, are many. The highest among them all is self-restraint. Those amongst the ancients that were acquainted with truth said that self-restraint leads to the highest merit. As regards the Brahmana in particular, self-restraint is his eternal duty. It is from self-restraint that he obtains the due fruition of his acts. Self-restraint, in his case, surpasses (in merit) charity and sacrifice and study of the Vedas. Self-restraint enhances (his) energy. Self-restraint is highly sacred. Through self-restraint a man becomes cleansed of all his sins and endued with energy, and as a consequence, attains to the highest blessedness. We have not heard that there is any other duty in all the worlds that can equal self-restraint. Self-restraint, according to all virtuous persons, is the highest of virtues in this world. Through self-restraint, O foremost of men, a person acquires the highest happiness both here and hereafter. Endued with self-restraint, one acquires great virtue. The self-restrained man sleeps in felicity and awakes in felicity, and moves through the world in felicity. His mind is always cheerful. The man who is without self-restraint always suffers misery. Such a man brings upon himself many calamities all born of his own faults. It has been said that in all the four modes of life self-restraint is the best of vows. I shall now tell thee those indications whose sum total is called self-restraint.

In the body restraint is good, good is restraint in speech, in thought restraint is good, good is restraint in all things. A Bhikshu, restrained in all things, is freed from all pain.

And to knowledge temperance; and to temperance patience; and to patience godliness;

Krishna. Hero long-armed! beyond denial, hard Man's heart is to restrain, and wavering; Yet may it grow restrained by habit, Prince! By wont of self-command. This Yog, I say, Cometh not lightly to th' ungoverned ones; But he who will be master of himself Shall win it, if he stoutly strive thereto.