Enchiridion 32

When you have recourse to divination, remember that you do not know what the issue is going to be, but that you have come in order to find this out from the diviner; yet if you are indeed a philosopher, you know, when you arrive, what the nature of it is. For if it is one of the things which are not under our control, it is altogether necessary that what is going to take place is neither good nor evil. Do not, therefore, bring to the diviner desire or aversion, and do not approach him with trembling, but having first made up your mind that every issue is indifferent and nothing to you, but that, whatever it may be, it will be possible for you to turn it to good use, and that no one will prevent this. Go, then, with confidence to the gods as to counsellors; and after that, when some counsel has been given you, remember whom you have taken as counsellors, and whom you will be disregarding if you disobey. But go to divination as Socrates thought that men should go, that is, in cases where the whole inquiry has reference to the outcome, and where neither from reason nor from any other technical art are means vouchsafed for discovering the matter in question. Hence, when it is your duty to share the danger of a friend or of your country, do not ask of the diviner whether you ought to share that danger. For if the diviner forewarns you that the omens of sacrifice have been unfavourable, it is clear that death is portended, or the injury of some member of your body, or exile; yet reason requires that even at this risk you are to stand by your friend, and share the danger with your country. Wherefore, give heed to the greater diviner, the Pythian Apollo, who cast out of his temple the man who had not helped his friend when he was being murdered.

Epictetus, Enchiridion 32, translated by W. A. Oldfather

When you have recourse to divination, remember that you do not know how it will turn out, but that you are come to inquire from the diviner. But of what kind it is, you know when you come, if indeed you are a philosopher. For if it is any of the things which are not in our power, it is absolutely necessary that it must be neither good nor bad. Do not then bring to the diviner desire or aversion (ἔκκλισιν): if you do, you will approach him with fear. But having determined in your mind that every thing which shall turn out (result) is indifferent, and does not concern you, and whatever it may be, for it will be in your power to use it well, and no man will hinder this, come then with confidence to the Gods as your advisers. And then when any advice shall have been given, remember whom you have taken as advisers, and whom you will have neglected, if you do not obey them. And go to divination, as Socrates said that you ought, about those matters in which all the inquiry has reference to the result, and in which means are not given either by reason nor by any other art for knowing the thing which is the subject of the inquiry. Wherefore when we ought to share a friend's danger or that of our country, you must not consult the diviner whether you ought to share it. For even if the diviner shall tell you that the signs of the victims are unlucky, it is plain that this is a token of death or mutilation of part of the body or of exile. But reason prevails that even with these risks we should share the dangers of our friend and of our country. Therefore attend to the greater diviner, the Pythian God, who ejected from the temple him who did not assist his friend when he was being murdered.

Epictetus, Enchiridion 32, translated by George Long

When you make use of prophecy remember that while know not what the issue will be, but are come to learn you it from the prophet, you do know before you come what manner of thing it is, if you are really a philosopher. For if the event is not in our control, it cannot be either good or evil. Therefore do not bring with you to the prophet the will to get or the will to avoid, and do not approach him with trembling, but with your mind made up, that the whole issue is indifferent and does not affect you and that, whatever it be, it will be in your power to make good use of it, and no one shall hinder this. With confidence then approach the gods as counsellors, and further, when the counsel is given you, remember whose counsel it is, and whom you will be disregarding if you disobey. And consult the oracle, as Socrates thought men should, only when the whole question turns upon the issue of events, and neither reason nor any art of man provides opportunities for discovering what lies before you. Therefore, when it is your duty to risk your life with friend or country, do not ask the oracle whether you should risk your life. For if the prophet warns you that the sacrifice is unfavourable, though it is plain that this means death or exile or injury to some part of your body, yet reason requires that even at this cost you must stand by your friend and share your country's danger. Wherefore pay heed to the greater prophet, Pythian Apollo, who cast out of his temple the man who did not help his friend when he was being killed.

Epictetus, Enchiridion 32, translated by P. E. Matheson