What Judaism, Christendom, and Islam Have in Common: Theism

Excerpt from The Secular Outlook: In Defense of Moral and Political Secularism, by Paul Cliteur (Wiley-Blackwell, 2010). Reprinted with permission from the author.

From Chapter 4: Moral and Political Secularism

What Judaism, Christendom, and Islam Have in Common: Theism

Judaism, Christendom, and Islam differ in some aspects. But none of these differences can hide the one major similarity. This similarity concerns the concept of God upheld by Judaism, Christendom, and Islam. The “religions of the book” do not differ in their understanding of God. “At the heart of Islam stands the reality of God, the One, the Absolute and the Infinite, the Infinitely Good and All-Merciful, the One Who is at once transcendent and immanent, greater than all we can conceive or imagine, yet, as the Qur’an, the sacred scripture of Islam, attests, closer to us than our jugular vein.”[47]

So far we have, in the eyes of an Islamic writer, some elements that characterize Islam. But these are not unique to Islam. The same may be said of Judaism and Christianity. The idea of God outlined here is that of the theistic god.[48]

As we shall see, it is also important for Christianity, Judaism, and Islam to be labeled the “Abrahamic religions.” All three recognize Abraham as a forefather.[49] Likewise, Judaism, Christendom and Islam are labeled “theistic religions” because all three subscribe to “theism,” the belief in a single god with the characteristics outlined above.

The American historian of the Middle East Bernard Lewis (1916– ) is right when he says that Islam, Judaism, and Christianity display quite a few similarities. Islam is much closer to the Judeo-Christian tradition than to Hinduism, Buddhism, or Confucianism. Judaism and Islam share the belief in a divine law thought to regulate all aspects of human life, even down to the food and drink we consume.

British philosopher Anthony Kenny (1931– ) stresses the same point. Not only do Jews and Christians share a common heritage, he writes in his book What I Believe (2006), but Christianity and Islam, too, have much in common.[50]

Both religions are monotheistic and universalist. Both traditions recognize the Hebrew Scriptures as inspired texts, bearing a message from God that has been suspended by later, definitive revelation. Members of all three faiths appeal to their own sacred texts to guide or justify their actions of the present day, and within each tradition there are many different methods and procedures by which the ancient sayings are linked to the conditions of modern life.[51]

That similarity is welcomed by many as the basis of a common ethic. In 1908 philosopher L.T. Hobhouse (1864–1929) wrote: “With regard to the standard, as opposed to the basis of morals, all forms of monotheism have something in common. God is the father of all. Therefore, all men are brothers, and should be members of one Church.”[52] But only a few lines further that commonality seems to evaporate because although this “potential universalism,” as Hobhouse called it, is common to Islam and Christianity, he censured the Jewish religion for its “national exclusiveness.” And in continuing his analysis Hobhouse had to acknowledge that Christianity “has really more affinity with Buddhism.”[53]

Besides, not all that the theistic creeds have in common can be considered to be great contributions to a basis for living together with non-believers. Lewis points out that Christians and Muslims also share some form of “triumphalism,” seeing themselves as the chosen standard-bearers of God’s one true message, a message they are expected to pass on to the rest of mankind. Christendom and Islam “are in many ways sister civilizations, both drawing on the same shared heritage.”[54]

For much of their shared history Christendom and Islam have fought one another, and yet, Lewis writes, “even in struggle and polemic they reveal their essential kinship and the common features that link them to each other and set them apart from the remoter civilizations of Asia.”[55]

From a Muslim perspective, Judaism and Christendom are forerunners of Islam. But the scriptures of the Jews and Christians, although based on authentic sources, are incomplete. These scriptures have, as it were, been “overtaken” by Islam. Islam has incorporated the true elements of Christendom and labeled as untrue those elements that have not been incorporated.[56]

British philosopher John Haldane (1954– ) writes that theism “is the belief in a single, all-knowing, all-good, all-present, and all-powerful, eternally existing God who created and sustains the universe.”[57] He adds that, more specifically, he has in mind the so-called “Abrahamic faiths” or “religions of the book”: Judaism, Christianity, and Islam. These descriptions derive from the account given in the Torah (the first five books of the Hebrew Bible). All three religions recognize the authority of the Hebrew Bible as the word of God to humankind, Haldane writes.[58]

(Credit: Phillip Medhurst Bible Pictures / Flickr)
(Credit: Phillip Medhurst Bible Pictures / Flickr)

This is in line with other definitions of theism (or monotheism) that were presented in Chapter 1. Yet there is a problem. In Chapter 2, I discussed the story of Phinehas, who punished his fellow Israelites for their worship of the wrong gods. In a previous section of that same chapter we saw that Deuteronomy 13:1–3 gives “a warning against idolatry.” Here is the relevant quote again:

If a prophet or a dreamer of dreams arises among you and gives you a sign or a wonder, and the sign or wonder that he tells you comes to pass, and if he says, “let us go after other gods,” which you have not known, “and let us serve them,” you shall not listen to the words of that prophet or that dreamer of dreams.

This is only understandable if “going after other gods” was a common practice among the Israelites, so apparently there were other gods besides Yahweh. The biblical injunction “You shall walk after the Lord your God and fear him and keep his commandments and obey his voice, and you shall serve him and hold fast to him” (Deuteronomy 13:4–5) only makes sense against the background of a situation where there are also other gods around. As William Wainwright writes:

Most mainstream Old Testament scholars believe that the religion of the early Israelites was neither monotheistic nor polytheistic but “monolatrous.” While the existence of other gods was not denied, Israel was to worship no god but Yahweh.[59]

One can also say that the religion of Israel was “incipiently” monotheistic from its Mosaic beginnings, Wainwright says.[60]

In the first five books of the Bible there is little suggestion of monotheism. Yahweh issues commands as: “You shall have no other gods besides Me” (Exodus 20:3, Deuteronomy 5:7). Moses is told: “you must not worship any other god, because the Lord, whose name is Impassioned, is an impassioned God” (Exodus 34:14). Here we do not find a denial that there are other gods; the only message is that they are not to be worshipped by the Israelites.

Also in other places of the Bible Yahweh is introduced as “the God of Abraham, the God of Isaac, and the God of Jacob” (Exodus 3:6). As philosopher of religion B.R. Tilghman rightly says: “In all these dealings and introductions there is … no suggestion of monotheism.”[61]

This all changed when the Babylonians conquered the kingdom of Judah in 587 BCE. The religion of Yahweh underwent a crisis. The city of Jerusalem was partly destroyed, and so was the temple of Solomon. Prominent Israelites were taken to Babylon as hostages. This presented a new problem. How could Yahweh be worshipped if his temple no longer existed? When his powers were primarily local, how could he be worshipped in a foreign land? As a result of this, a new conception of Yahweh developed and by the end of the Babylonian captivity Judaism was “unequivocally monotheist.”[62] Yahweh was no longer the deity of a local people, but the God of the whole world who can be worshipped anywhere. This new idea of God is to be found in Isaiah 45:5: “I am the Lord, and there is no other, Besides me there is no God.”[63] This mature theistic concept of god (or God) is the focus of this book.

Excerpted from The Secular Outlook by Paul Cliteur. Copyright © Paul Cliteur, 2010. All rights reserved.

[47] Hossein Nasr, Seyyed, The Heart of Islam. Enduring Values for Humanity, Harper Collins, San Francisco 2004, p. 3.

[48] A frequently made observation is that Islam is more consistently monotheistic than Christendom, because Islam has no concept of the trinity. On this subject, see: Haeckel, Die Welträtsel, p. 363.

[49] Kuschel, Karl-Josef, Streit um Abraham. Was Juden, Christen und Muslime trennt und was sie eint [The Dispute about Abraham. What Divides Jews, Christians and Muslims and What Unites Them], Patmos 2001; Feiler, Bruce, Abraham. A Journey to the Heart of Three Faiths, William Morrow 2002.

[50] Kenny, What I Believe, p. 55.

[51] Ibid., p. 56. There are also authors who emphasize the differences between the three theistic religions. See: Weigel, George, Faith, Reason, and the War against Jihadism: A Call to Action, Doubleday, New York 2007, p. 21 referring to the fact that Islam takes a radically supersessionist view of both Judaism and Christianity “claiming that the final revelation to Muhammad de facto trumps, by way of supersession, any prior revelatory value (so to speak) that might be found in the Hebrew Bible or the Christian New Testament.”

[52] Hobhouse, L.T., Morals in Evolution: A Study in Comparative Ethics, Part II, Chapman and Hall, London 1908, p. 148.

[53] Ibid.

[54] Lewis, Bernard, The Crisis of Islam. Holy War and Unholy Terror, Weidenfeld & Nicolson, London 2003, p. 4.

[55] Ibid., p. 5.

[56] Lewis, Bernard, What Went Wrong? The Clash between Islam and Modernity in the Middle East, Weidenfeld and Nicolson, London 2002, p. 36. Some believe this is why Islam seems disinclined to develop further. See Constant, Benjamin, “De la religion considérée dans la source, ses formes et ses développements” [Of Religion Considered in Its Source, Forms, and Developments] in: Benjamin Constant, Oeuvres, ed. Alfred Roulin, Éditions Gallimard, Paris 1957, pp. 1365–1395, p. 1373. Constant says of Islam that it is the most static religion. Alexis de Tocqueville is even more critical of Islam. In their correspondence, he reproaches his friend Gobineau, whom he believes to have developed a certain unwarranted sympathy for Islam. See Tocqueville’s letter to Gobineau dated October 2, 1843 in: Tocqueville, Alexis de, and Gobineau, Arthur de, Correspondence entre Alexis de Tocqueville et Arthur de Gobineau, 1843–1859, Librairie Plon, Paris 1909, p. 24. On Tocqueville and religion: Cliteur, Paul, “A Secular Reading of Tocqueville,” in: Raf Geenens and Annelien de Dijn, eds., Reading Tocqueville: From Oracle to Actor, Palgrave, Macmillan, Basingstoke 2007, pp. 112–132.

[57] Haldane, John, An Intelligent Person’s Guide to Religion, Duckworth Overlook, London, 2003, p. 17.

[58] Ibid., p. 18.

[59] Wainwright, William, “Monotheism,” in: Stanford Encyclopedia of Philosophy, in: http://plato.stanford.edu, 2005, pp. 1–23, p. 1.

[60] Ibid., p. 2. See also: Tilghman, B.R., An Introduction to the Philosophy of Religion, Blackwell, Oxford 1994, p. 30 and Nikiprowetzky, V., “Ethical Monotheism,” in: Daedalus, 104, no. 2, Revelation, and Doubt: Perspectives on the First Millenium B.C., (Spring, 1975), pp. 69–89, p. 76.

[61] Tilghman, Introduction, p. 29; Nikiprowetzky, “Ethical Monotheism”, p. 78.

[62] Tilghman, Introduction, p. 30.

[63] Nikiprowetzky, Ibid., p. 82 writes: “Radical monotheism is unambiguously present … in the doctrine of the Second Isaiah.”

Paul Cliteur is professor of Jurisprudence at Leiden University, the Netherlands. He was also professor of Philosophy at the Delft University, the Netherlands (1995-2002), and visiting professor of Philosophical Anthropology, Ghent University, Belgium (2014). Prof. Cliteur’s research is in the field of ethics, the philosophical foundations of the law, more in particular moral dilemmas around multicultural society, fundamental rights and the relationship between law and worldviews. He is the author of The Secular Outlook (Wiley-Blackwell, Chichester, 2010).

The Secular Outlook: In Defense of Moral and Political Secularism
By Paul Cliteur
Wiley-Blackwell; 1 edition (13 August 2010)
ISBN-10: 1444335219
ISBN-13: 978-1444335217

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  1. In common?
    Child abuse!
    Abuse of women's rights; all human rights.
    Lies, and more lies to defend the original lies.


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