This is looking a little further ahead to events yet to be related. By that time the followers of the two religions had become people of two different races: Judaism followed almost exclusively by Jews who were Semites; Christianity by Aryans, Greeks, Romans and other Europeans. This racial distinction became the final barrier which completely separated them.
Note.
Aryans and Semites:
Not all Semites are Jews, for example the Arabians; nor are all Aryans Christians p. e. the Persians. Religious and racial lines are no longer identical.
Theme for discussion:
Why did most heathen converts to Judaism ultimately become Christian?