Answer:
The fundamental belief of Judaism and Christianity referred to in the above statement is monotheism.
Step-by-step explanation:
- Both Judaism and Christianity are the branches of a single tree as the ancestry of both the religions can be traced back to a single entity.
- A monotheistic religion is the one in which the followers of the religion worship only one God. It preaches that the God is only singular and is present in a single original form.
- The God may choose to reach his subjects through various means and through multiple people called messengers at the same time, but God himself does not exist in multiple forms.