Whatever your mission, stick by it as if it were a law and you would be committing sacrilege to betray it. Pay no attention to whatever people might … - Epictetus

Whatever your mission, stick by it as if it were a law and you would be committing sacrilege to betray it.

But shall he argue, indeed, and then not take pains to avoid conducting himself recklessly and at haphazard in an argument? And if he does not, how will he any longer be the sort of man we think he is? (...) Let them show that he will be able, and all these speculations become mere superfluity, they were absurd and inconsistent with our preconception of the good man.

Die Natur hat dem menschen eine Zunge, aber zwei Ohren gegeben, damit er doppelt so viel hört, wie er spricht.

understand that every event is indifferent and nothing to you, of whatever sort it may be; for it will be in your power to make a right use of it, and this no one can hinder.