Christianity is a cult started by Jewish people.Well, Judaism of course was a recognized religion, one of Jewish customs, but how can your reason out that so it is quite likely that the "Jewish custom" referred to is Christianity (why not just Judaism)?
First, a likely cause for investigation erupted right in Tacitus' backyard, so to speak, in Rome c. 95 A.D. Emperor Domitian's niece Domitilla, and her husband Flavius Clemens, were accused of "atheism," related to "being carried away into Jewish customs." Judaism of course was a recognized religion, so it is quite likely that the "Jewish custom" referred to is Christianity [Benk.PagRo, 15-16]. Here, then, was a perfect motive for Tacitus to investigate the movement historically. Some of Rome's highest-placed people seem to have joined the movement.
Tacitus and Jesus. Christ Myth Refuted. Did Jesus Exist? A Christian Response
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