The Enchiridion (49-50)

When any one shows himself vain, on being able to understand and interpret the works of Chrysippus, say to yourself: Unless Chrysippus had written obscurely, this person would have had nothing to be vain of. But what do I desire? To understand Nature, and follow her. I ask, then, who interprets her; and hearing that Chrysippus does, I have recourse to him. I do not understand his writings. I seek, therefore, one to interpret them. So far there is nothing to value myself upon. And when I find an interpreter, what remains is to make use of his instructions. This alone is the valuable thing. But if I admire merely the interpretation, what do I become more than a grammarian, instead of a philosopher, except, indeed, that instead of Homer I interpret Chrysippus? When any one, therefore, desires me to read Chrysippus to him, I rather blush, when I cannot exhibit actions that are harmonious and consonant with his discourse.

Whatever rules you have adopted, abide by them as laws, and as if you would be impious to transgress