James in Acts 21:20 says « many tens of thousands » Jews came to Jesus but this is from bias altered.

James says many « myriads » — a word in English and Greek meaning « tens of thousands » – of Jews have come to faith, and are « zealous for the Law. »

We canvass all the leading Bibles, and the leading commentaries, and we can deduce there is a real bias issue, against Jews in particular. To give them credit for success is so begrudging, a simple Greek word « myriad » – meaning literally the number 10,000 in Greek, is manipulated, to read most often as « many thousands. » This is wholly unwarranted.

As two commentators mention, the Jews from all over the mediterranean were returning to Jerusalem for the Pentecost festival, and hence is it not that improbable that Christianity had many tens of thousand converts over the first 25 years. But some commentator was venomous in his anti-semitism, and begrudgingly acknowledged their initial role. There is more to Bible translation than meets the eyes. Mistranslations can creep in from prejudice, or to support a cause, e.g., promote Paul.