What About Jews Who Don't Believe in Jesus?
When understanding the New Testament, it is important that readers become aware that the focus of much of the texts (ie: the Epistles) are largely dedicated to the messages from Paul to specific groups of gentiles among various communities in the Roman Empire. Often, these were home-based communities, or larger synagogue communities of which the Gentiles were a part of. With such emphasis on providing insight and guidance to the nations, what is missing is technical guidance on 'how' this movement would have impacted the Jews in those communities.
Specifically, for the Jews based in the temple area in Jerusalem and other parts of Israel - how they were integrating this knowledge into their Jewish liturgical and traditional observance is mostly absent. For instance, we see glimpses that there were communities in Israel, including the one James and Peter were involved in, though we get nothing else on how this looked from day to day.
We see references to the holidays, and that the apostles, including Paul, still observed them - but we don't have insight to what (if anything) was different from the rest of the Jewish world. By all indications, not much had changed on a practical level. Many believe this is because the framework was already set for the Jewish people through the Torah and the Jewish traditions.
