Philo Judaeus In Flaccum 50

[50] For if we were to neglect the opportunity of adhering to our national customs when it is afforded to us, we should deserve to meet with the severest punishment, as not giving any proper or adequate return for the benefits which we have received; but if, while it is in our power to do so, we, in conformity with our own laws which Augustus himself is in the habit of confirming, obey in everything, then I do not see what great, or even what small offence can be laid to our charge; unless any one were to impute to us that we do not transgress the laws of deliberate purpose, and that we do not intentionally take care to depart from our national customs, which practises, even if they at first attack others, do often in the end visit those who are guilty of them.