Philo & the Mit’yav’nim
A Jewish parallel is mityahadim, “those who became like Jews” (Esther 8:17), though some translators believe that this word may be better translated, “those who took the part of the Jews”.
The problem of the mit’yav’nim is that they tended to bring heathen ways into Judaism, forsaking the Torah or rather giving the Torah a hellenistic interpretation.
An example is Philo of Alexandria, the Alexandrian Jewish philosopher, who tended to allegorise the mitzvot and remove their traditional character and authority in favour of symbolism without the symbol.