An Historian’s Approach to Religion is divided into two parts. The first charts the evolution of religion. From the earliest manifestation in nature worship, Toynbee notes a shift to worshipping local communities represented by the deification of the city-state (like Athens or Sparta). Eventually this local identity succumbed to worship of ecumenical communities, generally incarnated in a ruler (as the emperors of Rome were deified) before the worship of external deities. The benefit of external deities was that they offered external and transcendent authority. This progressed to liberating humanity from the natural world through worship of the philosopher and represented the self-sufficiency of humankind and the deification of human power. Ultimately, however, this failed to address the shortcomings of society and the needs of the masses, because humanity continued to be driven by self-centredness; either individual or communal. According to Toynbee, ‘the members of a disintegrating society whose normal human sufferings have been intensified to an abnormal degree by the social breakdown and disintegration resulting from the failure of parochial-community-worship’ gave rise to the higher religions. These higher religions, exemplified according to Toynbee in Christianity and Mahāyāna Buddhism, offered a way blazed by a supreme being, centred the universe beyond the self and, most important, accepted suffering as good. As such, their great contribution to human history is their direct challenge to humanity’s ‘worship of collective human power’.

The rise of the higher religions represented a new epoch in human history, yet they came to face fundamental challenges with which they would struggle. For instance, in the face of persecution Christianity and Mahāyāna Buddhism thrived, yet when they no longer represented opposition to the old order they gradually lost their zest and were hijacked for ‘mundane’ purposes and empire building. Similarly, when faced with the intercourse of philosophy, Christianity and Islam consciously embraced being defined in terms of Hellenic metaphysics. This had the awkward consequence of the religions defining themselves in terms of truth. Since ‘Intellect progressively improves its comprehension of the Universe’s time, culture and scientific advances inevitably put great strains on the truth claims entrenched in metaphysical dogma. In order to free these traditions from unnecessary baggage, Toynbee calls for stripping Christian and Islamic religion ‘of their incongruous and outworn Greek scientific dress’; resisting the temptation to replace this with ‘an alternative scientific dress of a Western cut’; and to embrace the truth they espouse in their natural ‘non-scientific poetical sense’.

The second part of Toynbee’s significant work focuses on ‘Religion in a Westernizing World’ and the expansion of modern Western civilization across the globe, which he deems ‘the most prominent single feature in the history of Mankind during the last four or five centuries’. The consolidation of Western influence grew to its height in the seventeenth century and coincided with the rise of secularism. Thus it was secularism that Europe exported. The momentousness of this export is magnified tenfold by a consequence of the literally worldwide expansion of Western civilization and of its progressive reception, in its secularized form, by the non-Western majority of the human race. Toynbee argues that the forced conversions of the Spanish and Portuguese empires facilitated a fusion of cultures and stability that failed to emerge in the similar but less dogmatic endeavours of the English, Dutch and French. This is partly due to the fact that the Iberian missions occurred earlier, taking place under a unified religious sanction and within a more homogenous religious context less disturbed by Protestant disillusionment. The fracturing of Christendom was not, according to Toynbee, a wholly unique occurrence. It had been anticipated in the multiple revolutions against Mahāyāna Buddhism in China. The change in Europe rested on a rejection and fear of religious fanaticism and growing belief in human self-sufficiency found in technology. This precipitated a worldwide shift, under the influence of European colonialism, from religion to technology. The combination of religious toleration in the West and the increased necessity to adopt Western technology to keep pace with the militarized status quo during the eighteenth and nineteenth centuries quickened Westernization, as religion ceased to be a stumbling block between intercultural dialogues.

This process actually re-erected two of the early phases of human civilization. Whereas the rise of higher religions challenged the deification of community and worship of the philosopher, Western modernity reintroduced the empire and worship of their leaders (for example: Napoleon, Mussolini, Stalin, Hitler and Mao) and replaced the deification of the philosopher with the ‘idolization of the invincible technician’ (da Vinci, Hobbes, Newton and Bacon). Toynbee affirms this cyclical aspect of history repeatedly, while the rise of science was bolstered by the incorporation of technology from around the world. Toynbee alludes to the further cyclical nature of human history by suggesting that as humanity reaches ‘the limits of the scientific study of human affairs’ again the door may be opened for religion that is ‘spiritually more promising’.

The final two chapters address the twentieth-century context and interreligious dialogue. According to Toynbee the twentieth century brought a rejection of the idols of technology and empire and a renewed interest in religious experience. Moreover, the rigid division between Protestantism and Catholicism gave way to previously unknown middle ground between them, leading Toynbee to hypothesize the next step may be establishing common ground among Christianity, Judaism, Islam, Zoroastrianism, Hinduism and Buddhism. This, however, requires recognition that all the higher religions are both carriers of truth and historical entities shrouded in enculturation. Overcoming historical divisions will require ascertaining the true essence of these traditions, just as Jesuits in sixteenth-century Japan acted with ‘uncommon insight and courage’ to distinguish between the essence of true Christian faith and its ‘Western accidents’. This is a process of ‘winnowing away the chaff’ of nonessentials. For Toynbee, humanity’s ‘goal is to seek communion with the presence behind the phenomena, and to seek it with the aim of bringing [itself] into harmony with this absolute spiritual reality’. For this to happen faith traditions must be willing to sacrifice: theologies of exclusion held to by the minority, vacuous myths held by the majority, and most important the self-centredness that claims solely their own religions are right and true. For Toynbee, in this age the world’s living religions will be practically put to the test and will be ‘known by their fruits’.