Like many other philosophical terms, monotheism is a product of the 18th-century Enlightenment. It’s not that the belief in “one God” did not exist before then; it most certainly did. But that belief had never been named.
Today it is accepted that Judaism, Christianity and Islam are the world’s principal monotheistic religions. Most people probably also accept that the tenets of monotheism are drawn from the Bible. But as with so many ideas about the Bible, this is wrong, especially in the sense in which monotheism is generally understood today.
In recent years, the concept has been subjected to some rigorous study and examination. Just as many other ideas were originally expressed very simply, monotheism appears to have become a much more complex idea over time.
Today those who study it define the concept in a variety of ways: hard or soft, exclusive or inclusive, or shades in between. Not surprisingly, the three major representatives of monotheism do not make identical claims. Islam practices “exclusive monotheism.” To the Islamic world, only Allah is God. No other god exists. For followers of Judaism, it is “inclusive monotheism.” Other gods can exist, but they amount to nothing and the God of Israel is the only god to be worshiped. Christianity straddles the fence. Most Christians would be hard put to explain how their religion is monotheistic and recognizes three beings in the one God.
Furthermore, the ideas generally expressed as monotheism find their origin not at Mount Sinai, as most Jews and Christians would contend, but in the reasoning of Greek philosophers such as Plato and Aristotle. For them the tenets of monotheism were encapsulated in the supreme first cause.
What, then, of the claims of Judaism and Christianity to be monotheistic religions? Jewish scholars have long realized that there was a difference between the ideas of a deity in the Tanakh (the Jewish Scriptures) and the subsequent reasoning of the rabbis. Various people have tried to categorize the Jewish approaches to monotheism and the reasons for their changes. In the same vein as inclusive monotheism, some have proposed “hierarchical monotheism,” with the God of Israel being the ultimate God. The gods of other nations could exist, but the only one that Israel was to worship was their God. He reigned supreme over the other gods.
This allowed other divine beings to exist. In fact, the idea of a grand vizier or supreme ruler under God has long been considered a part of the Scriptures. An appreciation of that helps explain why the mainly Jewish early New Testament church of the first century could so easily accept Jesus not only as a messiah but as a divine being. To them, there was no contradiction of terms or philosophical reasoning.
But first- and second-century Judaism, in adjusting to the destruction of the temple in 70 C.E., had more than the followers of Jesus Christ to deal with. Shortly after the loss of the temple, and then the denial of access to Jerusalem after the Bar Kokhba revolt in 136 C.E., Judaism had to contend with the rise of Gnostic religions and Zoroastrianism from the East. To deny the claims of these groups, the rabbis opted to change their understanding of monotheism. They replaced hierarchical monotheism with the Greek philosophical concept of “ontological monotheism.” Plato’s idea of a supreme first cause was the embodiment of ontological monotheism. As the study of “being,” ontology introduced the current notion of one God as a single being into the religion of the Jews.
For Christianity, the whole debate over Christology and the nature of God that consumed and divided the church through the second through fourth centuries was an attempt to harmonize Scripture with Greek monotheistic ideas based on ontology. Like other such attempts at harmonization, it resulted in much bloodshed, misunderstanding and confusion.
In a future article, we will explore more fully the understanding of the New Testament writers on this subject.