What ancient civilization practiced monotheism?

Answer 1

The only ancient monotheism was Judaism, from Abraham onward. For Jews, that is a religious truth and is stated by Maimonides based on the Torah and tradition.

• Link: How Abraham founded monotheism

What about the Ancient Egyptians or Zoroastrians? In both cases, these were monolatrous henotheistic faiths. This means that they had multiple divinities with powers not completely constrained by other divinities.
Ancient Persia:
There is no consensus on when Zoroaster lived. Zoroastrianism is unlikely to be older than Judaism, and in addition Zoroastrianism is by most standards a duotheism.
ancient Egypt:
In the case of Atenism, although all of the heavenly gods were reduced to Amun-Re, the Pharaoh was himself still held to be a god.

• Link: Were the Israelites monotheistic

Link: What do Jews believe about God?

Answer 2

1a) The first continuous monotheistic tradition and religion as we know it, was and is Judaism, the tradition founded by Abraham. It began 3800 years ago, and its founding principle is that God is One. This was well before the Egyptian king Akhenaten, who in any case (according to tradition) was influenced by Israelite beliefs.
1b) Some might claim that monotheistic Judaism started later, as (for example) King Josiah made reforms in the late First Temple period. However, this is the view of secular academe, and flies in the face of tradition. Judaism had already been monotheistic for eight centuries by the time of Josiah. All he did was to eradicate the idolatrous influences of those Jews who had strayed from their own religion. This had happened repeatedly (such as with Jehoshaphat [2 Chronicles 17:6], and Samuel before him [1 Samuel 7:3-4]); and those who strayed into pagan practices never encompassed the entire people.

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2) Zoroastrianism, which might be suggested as another early contender, is not such a clear matter. There is no consensus on when Zoroaster lived. Moreover, the Zoroastrians believed in two gods, not one. The Jewish Sages who collated the Talmud in the early centuries of the Common Era lived in Babylonia, witnessed the practices of the Zoroastrians, and recorded this fact (Talmud, Sanhedrin 39a). In addition, in Zoroastrianism:

• there is worship through intermediaries, who are themselves "worthy of worship"
• evil and good each has its own creator
• some of its adherents believe in a self-creating universe
• some modern scholars see it as a form of pantheism.

Answer 3

The ancient civilization that practiced monotheism was ancient Egypt under the rule of Pharaoh Akhenaten during the 18th Dynasty. Akhenaten promoted the worship of the sun god Aten as the sole deity, rejecting the traditional polytheistic beliefs of Egypt.

Answer 4

Middle-Eastern religions

Answer 5

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