The most intellectually satisfying book of philosophy I've read on Marx's concept of religion is Nicholas Lash's A Matter of Hope: A theologians reflections on the thought of Karl Marx, (Darton, Longman and Todd,1981). Lash is Roman Catholic philosopher-theologian in dialogue with Marx's thought from the standpoint of critical theology.
(image: Exodus - Bernard Deshler)
Lash is certainly correct when he writes that Feuerbach's account of the "essence" of Christianity is very weak, as well as elitist/classist. He points to Feuerbach's question in giving primitive christianity failing grades : "Did Christianity conquer a single philosopher, Historian or poet of the Classical period? The philosophers who went over to Christianity were feeble contemptible philosophers...The decline of culture was identical with the victory of Christianity" (Essence of Christianity, p 269). Surely this sort of class chauvinism and valorisation of 'noble Rome' coloured Feuerbach's whole evaluation of the character of 'Primitive Katholizismus'.
Feuerbach's condemnation of primitive Christianity is based on a very speculative and dismissive reading: he states that the images of God or Christ or the kingdom,- that is the material content of christan religious faith, - were the fanciful pre-conceptual projections of human self-understanding. So religion for Feuerbach is human alienation from itself. Marx took this theory as his own. Marx's historical method and empathy surpassed Feuerbach's, and permitted him to see religion and real human suffering in a grounded, original manner: viz. Marx's statement in his Introduction to A Contribution to the Critique of Hegel’s Philosophy of Right that religion is: "the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions. It is the opium of the people." But still Marx's theoretical reliance on Feuerbach for a theory of religion and Marx's own formal and nominal early religious instruction allowed a certain reductionism to remain (religion as only and merely a fantastic reflection of human alienation).
Marx assuming Feuerbach's central thesis , went on in his outline of the transit to the socialist-communist society to state that religion possessing no content of its own and being merely a projection born of human alienation, would wither away with the State in socialist society. Marx unlike Feuerbach was not elitist about the religion of the people, but he did not develop an analysis of the social contradictions within the composition of early christianity as Engels did, and neither Marx nor Engels dealt with the power of "utopia' in the Bible. The 20th century Marxist philosopher Ernst Bloch of The Frankfurt School accomplished this retreival in his investigations of the religions of the people, and his explorations mark a great advance in a Marxist theoretical recovery of the revolutionary iconoclastic use of the prophet's scrolls, Jesus' iconoclastic way. Bloch's thesis in his work Atheism in Christianity is that there are virtually two canons of Scripture, or two Bibles – one interpreted by a church compromised by union with the ruling-class and used in order to dominate the masses from above, and the other a religion of the people, and providing the utopian social-revolutionary aspect of christianity.
Thomas Aquinas, the angelic doctor of scholasticism made extensive use "Apophatic" theology (from Ancient Greek root meaning"to deny") — also known as negative theology or via negativa, in his opus Summa Theologica. This is a theology that attempts to describe God, the Divine Good, by negation, that is to say only of what may not be said about the ineffable mystery of God. . Apophatic theology found its most influential expression in works such as those of Pseudo-Dionysius , an author Aquinas quotes extensively in ST. Aquinas states that all mediations/symbolisations of the divine such as the sacraments will cease with the coming of the beatific vision in the fullness of 'the kingdom of God'.
In contrast to the modern "New Atheism" tendency of bourgeois secularism found in the writings of Richard Dawkins, Christopher Hitchens and Sam Harris, the Frankfurt School thinkers are aware that Christian theological reflection and Christian institutions of religion form the main root of Western culture and moral norms. Consequently, they recognize religion as a pre-eminent tool of cultural criticism, and they acknowledge negative theology as an authentic form of reason.
So within christianity we find not only the anthropomorphic tendency of an alienating religion but also a tradition of the prophetic voice as well as an apophatic Mystical theology with its language of negation regarding the limitations of symbols. Both these christian currents reject the fetishism of penultimate forms and open the 'religion and revolt' question afresh for atheist and theist alike..
1.Marx, K. Introduction to A Contribution to the Critique of Hegel’s Philosophy of Right.Collected Works, v. 3. New York.1976
2. Lash, Nicholas. Matter of Hope : A Theologian's Reflections on the Thought of Karl Marx. 1982. Univ. of Notre Dame Press, Notre Dame, IN.
3. Bloch, Ernst Jun 1 2009. Atheism in Christianity: The Religion of the Exodus and the Kingdom.With an Introduction by Peter Thompson;
Translated by J. T. Swann. 2nd edition. Verso.
4. Aquinas, Thomas. Summa Theologica, Translated by the Fathers of the English Dominican Province. Benziger Bros. edition. 1947-8. Note: cf. see "Of the Necessity of The Sacraments" (Four Articles)
5. Feuerbach, Ludwig. The Essence of Christianity. Foreword by Helmut Richard Niebuhr; Introduction by Karl Barth. HarperCollins, 1942.