Now the traditional academic answer is sometime after Titus’s little visit to Jerusalem ( I’ll ignore theological answers except for the purposes of historical record), and we see Tacitus refer to Christians as being distinct from Jews, ( I think Josephus’s references are thought a pious forgery) in about 110 AD. I think Paul ended adherence to dietary laws and circumcision. But, there were several sects in Judea at the time with radically different views from the mainstream and they tended to be considered Jewish by outsiders and themselves, if not by most Jewish persons. In addition, the early Church continued to follow Sabbath on Saturday till Constantine and Passover was observed, though mostly in honour of the last supper, while Easter and Christmas were unknown for centuries.
The inclusion of a curse on the “Minim” which probably included Jewish Christians. According to the Jewish Encyclopedia article on Min: “In passages referring to the Christian period, “minim” usually indicates the Judæo-Christians, the Gnostics, and the Nazarenes, who often conversed with the rabbis on the unity of God, creation, resurrection, and similar subjects (comp. Sanh. 39b). In some passages, indeed, it is used even for “Christian”; but it is possible that in such cases it is a substitution for the word “Noẓeri,” which was the usual term for ‘Christian’… On the invitation of Gamaliel II., Samuel ha-Ḳaṭan composed a prayer against the minim which was inserted in the “Eighteen Benedictions”; it is called “Birkat ha-Minim” and forms the twelfth benediction; but instead of the original “Noẓerim” … the present text has “wela-malshinim” (=“and to the informers”). The cause of this change in the text was probably, the accusation brought by the Church Fathers against the Jews of cursing all the Christians under the name of the Nazarenes.”
Persecution of Jewish-Christians happened rather immediately after the death (and resurrection) of Jesus. The Apostles were hiding out in the Upper Room in which the resurrected Jesus appeared “for fear of the Jews.” The crowd turned against Jesus – “crucify him!”-- and the leaders who arranged for Jesus’ execution would likely turn on the Apostles, which they did when they started publicly claiming Jesus was raised from the dead.
St. Paul was an aggessive persecutor/prosecutor and was present at the stoning of St. Stephen. So, the separation was taking place rather immediately.
The destruction of the Temple in 70 AD is also another date used because after that, Jewish-Christians were universally no longer allowed in any synagogues, see the edict from the Council of Jamnia… prayers against the Christians were included in all (or most?) synagogues.
When the Spirit descended on Jesus as he was coming up out of the water.
Although the disciples didn’t know it until after the reserection , HIS ministry started and as far as I am concerned so did Christianity. YMMV and that is fine with me.
The fact that you mention this tells me several things: One, you accept the idea that Christianity did not come into existence suddenly, but developed over a long time. Second, you are unsure about the identity of a Christianity which still includes Passover, but does not yet include Easter.
It should now be clear that there was never one single event which can be referred to as “the break”, and that if you insist on getting an answer to your question, you’ll end up getting different answers from different people, which makes this question more suitable for GD than GQ. I’m not trying to be evasive or snarky. I honestly feel that you’re asking for opinions, not facts.
I believe the early Church in Jerusalum never thought if itself as anything but Jewiah, or at least the non Pauline version led by James did. After 70 AD most of them were either nailed to crosses (!) on the Jerusalum- Damascus road or slaves, and the Pauline version which had the most adherents outside Judea survived, which is why we have the destruction of the Temple as the date of the schism. But as I pointed out, even after this date, Christians continued to follow many Jewsih rituals and customs for centuries in some cases. The question therefore is, when did it begin to be considered as seperate from Judiaism by outsiders as well as adherents.
According to the wiki article on Easter, the first reference to Easter is in the mid-2nd century, and from the context, it appears to be referring to a well-established custom. By the end of the 2nd century, it was generally accepted as a practice of the disciples. So, I don’t know that it’s correct to say Easter was unknown for centuries.
Christmas is more ambiguous, but it seems to have been recognized by the 4th century, according to the wiki article. That’s not surprising, because Easter is the more important event, theologically.
But to answer the OP question, there could be different answers, depending on the viewpoint of the Jews and Christians of the day. I could see some Jewish followers of Christ continuing to identify as Jews, but the general Jewish community rejecting that claim, because Christian theology was not consistent with the strict monotheism of Judaism.
There may be a parallel here with the position of Mormons today. Mormons assert that they are Christians, but that assertion is not accepted by all Christians, because of the significant differences in Mormon theology from mainline Christianity.
I have thought of the Mormon situation. But, most non Christians think of Mormons as Christians, perhaps a strange sect, but Christians nonetheless. In the case of Judaism and Christianity, by the second and third centuries even outsiders had begun to see Christians as separate from Judaism as seen by the fact that the Romans saw Christians as distinct from Judaism. The Romans (usually) tolerated Jews, they were less enthusiastic about Christians. When did that start to happen.
Isn’t that also true of other denominations? This Jew is under the impression that some Christians reject Roman Catholicism because they put too much emphasis on Jesus, and some reject Unitarianism because they put too little emphasis on him. Perhaps that’s an oversimplification, but is it at least accurate enough to demonstrate that the question of “Who is a Christian?” has even more answers than “Who is a Jew?”
As Moriah pointed out at the beginning of the thread, the Jewish academy in Jamnia was identifying Christians as a separate group by the 90s, at the latest. The curses to which Moriah referred are quite probably directed at Jews who have left Judaism for Christianity, and not toward all Christians, but they clearly show a separation between the two groups. Similarly, the Gospel of John (90 - 120?) uses the word “Jews” throughout, where the Synoptics (70 - 95?) would specify Pharisees or the Sanhedrin or some other individual Jewish group, indicating that by the time that John was written, Christians looked on Jews as “other.” John also refers to Christians being expelled from synagogues for following Jesus.
I think that it is clear from those references that Christians and Jews had parted ways by the period 90 - 100, if not sooner.
As to the day of worship, The Acts of the Apostles (ca 90?) makes it clear that Christians were worshiping on the first day of the week (Sunday) by that time. As to the celebration of Easter, by 150, Christians were already fighting over whether to celebrate it in conjunction with the Jewish Passover or whether Christianity was to set its own dates for that feast. The “go it alone” crowd eventually won, but Irenaeus produced a letter chastising the bishop of Rome for overstepping his bounds by trying to punish those who were using the Jewish Passover to reckon the date.
Whatever Jewish practices may have continued into later centuries, (and many, in modified forms, continue, today), I would still set the period of 70 - 100 for the break, (which probably did not occur all at one time), while noting that it was absolute before 150.
Um, I’m unaware of any Christian group that rejects RC for over-emphasizing Jesus unless that group also rejects Protestantism & Eastern Orthodoxy- and denies both the Trinity of God & the Deity of Jesus. Of those groups, the most well known is probably the Jehovah’s Witnesses.