Why did Hadrian ban some rituals?

Answer 1

For a number of years in the First Century CE, a couple of Roman emperors (Hadrian and Vespasian) banned the practice of Judaism, at least in Judea. This was as a punishment against the Jews, the majority of whom were very religious. The Romans were attempting to crush the spirit of the Jews after the ill-advised attempts at rebellion by small groups of hotheads who flouted the circumspect advice of the Torah-sages (Talmud, Gittin 56a).Later, in the Fourth Century, Rome adopted Christianity and gradually became less and less tolerant of Judaism.

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More about the Romans and Judea