Final answer:
The Middle Kingdom of ancient Egypt aligns most closely with Abraham's beliefs, as this period emphasized a shift towards more communal religious beliefs and ethical values like justice and fairness.
Step-by-step explanation:
The ancient Egyptian era that has beliefs most similar to Abraham's beliefs would be the Middle Kingdom (c. 2030-1640 B.C.E.). During the Middle Kingdom, significant shifts occurred in religious practices, afterlife beliefs, and the kingship ideology. Rulers still claimed to be partly divine, but they also emphasized their humanity. An important belief system change relevant to this context is the rise of the funerary cult of Osiris, which came to dominate popular Egyptian religion in the Middle Kingdom, implying a more communal approach to the afterlife and a focus on the spiritual importance of ordinary people.
Considering that Abraham's beliefs arose from the context of Mesopotamian culture and emphasized monotheism along with ethical imperatives, the Middle Kingdom of Egypt's emphasis on justice and fairness, as well as a more inclusive spiritual focus, would be closer to Abraham's beliefs than the divine and centralized ruler concept of the Old Kingdom.