The Nazarenes become a Heretical Jewish Sect
As previously stated, the Nazarenes were Torah observant and within Judaism at first, but after a generation had passed with no return of their candidate for the messiah whom they asserted was still alive, they were labeled as a heretical Jewish sect for not giving up their belief in this same messiah. Gentile Christianity, not being part of Judaism, was not so labled, though anyone leaving the Jewish religion for another (Gentile Christianity was and is most certainly another religion), abrogating the eternal covenant, was an apostate to Judaism and is so today.
Around 85, the judgment was incorporated in the synagogue liturgy: 'May the Nazarenes and the heretics be suddenly destroyed and removed from the book of life.'
Maccoby's Revolution in Judea gives the inital view that the Nazarenes were labeled as heretics in 90 C.E. His later book, The Mythmaker revises this date to the time of the Bar Kokhba revolt.
Thus a new Jewish sect arose known as the Nazarenes under the leadership of....James, based on the belief in [J's] continued Messiahship. The Pharisees did not regard this sect as heretical. Indeed, the Nazarenes were regarded as being within the Pharisee party until about 90 [C.E.].
- (Revolution in Judea, p168, italics mine for emphasis)
And more:
The event, however, that weakened the Nazarenes fatally and gave the victory to the Paulinists was the siege and capture of Jerusalem by the Romans in 70 [C.E.]. The Nazarenes, as loyal Jews, took part in the defense of the city, and in the ensuing massacre most of them died. A few survived to continue an enfeebled existence... The remnants of the Nazarenes ... were regarded as heretics by the main body of Christians. To add to their miseries, they now for the first time came into conflict with their fellow-Jews, the Pharisees, who regarded the development of the anti-Semitic Christianity as proof that [Jesus/Yehoshua] could not have been the Messiah, and requested the Nazarenes to give up the Messianic belief that differentiated them from their follow-Jews In about 90 [CE] the Nazarenes were finally expelled from the Jewish Synagogue and became a heretical group in Judaism as well as Christianity. The Nazarenes continued to exist until about 400 [CE] declaring to the last that [Jesus/Yehoshua] was the Messiah, that he would soon return, that he was the Son of [G-d] but not divine himself, that the Jewish law had never been abrogated by him, and that Paul was a deceiver who had perverted [Jesus/Yehoshua's] message.
- (Revolution in Judea, p 181, italics mine for emphasis)
Further evidence that the Nazarenes were labeled heretics in Judaism comes from Maccoby's The Mythmaker in footnote 10 on page 219:
The common scholarly opinion that the Nazarenes were excluded from the synagogue in about 90 [CE] at the 'Synod of Javneh' by the formulation against them of the birkat ha-minim has been refuted by Kimelman (1981). The actual exclusion of the Nazarenes did not take place until the time of the Bar Kokhba revolt, in which the Nazarenes refused to take part.
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