Long and Sedley (pg. 374) comment:
"The most distinctive characteristic of Stoic ethics is its restriction of the ordinary Greek terms for 'good' and 'bad' to what we would call the moral sense of these words. In the case of 'good' this is expressed most generally by claiming that the only good thing is 'rectitude'...or 'the honourable'..."
Cicero: "Since that good is situated in what the Stoics call homologia ('agreement' will be our term for this, if you don't mind) - since it is in this, then, that that good consists to which everything is the means, that good which is the standard of all things, right actions and rectitude itself, which is reckoned the only good, though later in origin, is the only thing desirable through its intrinsic nature and value, whereas none of the first objects of nature is desirable for its own sake" (59D5, trans. Long & Sedley).
Sextus Empiricus: "The Stoics, sticking fast to the common conceptions so to speak, define the good as follows: 'Good is benefit or not other than benefit', meaning by 'benefit' virtue and virtuous action, and by 'not other than benefit' the virtuous man and his friend. For virtue, which is a disposition of the commanding-faculty, and virtuous action, which is an activity in accordance with virtue, are benefit directly. But the virtuous man and his friend, while also themselves belonging to goods, could neither be said to be benefit nor other than benefit, for the following reason. Parts, the sons of the Stoics say, are neither the same as wholes nor are they different from wholes; for instance, the hand is not the same as a whole man, since the hand is not a whole man, but nor is it other than the whole since the whole man is conceived as man together with his hand. Since, then, virtue is a part of the virtuous man and of his friend, and parts are neither the same as wholes nor other than wholes, the good man and his friend have been called 'not other that benefit'. So every good is taken in by the definition, whether it is benefit or not other than benefit" (60G, trans. Long & Sedley).
Epictetus, Discourses 3.3.2-4, trans. George Long
"The business of the wise and good man is to use appearances conformably to nature: and as it is the nature of every soul to assent to the truth, to dissent from the false, and to remain in suspense as to that which is uncertain; so it is its nature to be moved toward the desire of the good, and to aversion from the evil; and with respect to that which is neither good nor bad it feels indifferent. For as the money-changer is not allowed to reject Caesar's coin, nor the seller of herbs, but if you show the coin, whether he chooses or not, he must give up what is sold for the coin; so it is also in the matter of the soul. When the good appears, it immediately attracts to itself; the evil repels from itself. But the soul will never reject the manifest appearance of the good, any more than persons will reject Caesar's coin. On this principle depends every movement both of man and God."
Long, A. A., Sedley, D. N. (1987). The Hellenistic
Philosophers: vol. 1. translations of the principle
sources with philosophical commentary. Cambridge,
England: Cambridge University Press.