“Whatever moral rules you have deliberately proposed to yourself abide by them as they were laws, and as if you would be guilty of impiety by violating any of them. Don't regard what anyone says of you, for this, after all, is no concern of yours. How long, then, will you put off thinking yourself worthy of the highest improvements and follow the distinctions of reason? You have received the philosophical theorems, with which you ought to be familiar, and you have been familiar with them. What other master, then, do you wait for, to throw upon that the delay of reforming yourself?… Let whatever appears to be the best be to you an inviolable law.”
50
The Enchiridion (c. 135)
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Epictetus 175
philosopher from Ancient Greece 50–138Related quotes

Sunan Abu-Daud Book 11, Hadith 2139 http://www.searchtruth.com/book_display.php?book=11&translator=3&start=44&number=2138#
Sunni Hadith
Context: Narrated Mu'awiyah al-Qushayri: I went to the Apostle of Allah (peace_be_upon_him) and asked him: What do you say (command) about our wives? He replied: Give them food what you have for yourself, and clothe them by which you clothe yourself, and do not beat them, and do not revile them.

“First say to yourself what you would be; and then do what you have to do.”
Book III, ch. 23.
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