After the start given by the classical authors (in particular Durkheim and Weber, but also Simmel and W. James) to the scientific approach aimed at the knowledge of the religious fact, subsequent scholars have ventured, firstly, into the examination of religious practice (in the 1950s and 1960s) and then into the vexata quaestio of secularisation [1,2], a topic that has held sway for several decades, until the end of the last century and the beginning of the new millennium (the peak of interest was recorded between the second part of the sixties and the first part of the seventies). Subsequently, but particularly since the 1980s, the discourse on the post-secular or post-secularisation has developed [3,4,5]. Thus, albeit by way of contrast, the topic of secularisation has remained central even in the new millennium [6]. In the meantime, however, other research has been conducted on entirely new (or almost new) topics: prayer [7], spirituality [8,9], Eastern religions [10] and Chinese religions in particular [11,12,13,14], everyday [15] and/or lived religion [16], digital religion [17,18,19], gender [20], visual analysis [21,22], the phenomenon of megachurches [23,24,25,26], televangelism [27], Protestantism [28], atheism [29,30,31] and so-called nones [32,33]. Finally, in some cases, there has been a slide (understood as a fact and certainly not as an evaluation) towards para-religious or quasi-religious aspects, like in studies on Scientology [34,35], UFOs [36] or Pastafarians [37] (pp. 132–140) [38]. These contents were previously absent or poorly considered and are now visibly emerging, occupying the spaces of the most important journals, dedicated encyclopaedias and series. If the beginnings were characterised by a rather confessional propensity (for example, what is now the journal Sociology of Religion was called American Catholic Sociological Review from 1940 to 1963 and Sociological Analysis from 1964 to 1992), then gradually religious sociology became sociology of religion and ultimately of religions. In this regard, the diachronic dynamics of the original Conférence Internationale de Sociologie Religieuse (1948), which then became the Conférence Internationale de Sociologie des Religions (1981), and finally the Société Internationale de Sociologie des Religions (1989), is exemplary.

Sociologies from countries that have not been present in the past are beginning to appear on the international scene just now, either because of language barriers or because of difficulties in entering international publishing, especially in English. There are three main reasons for the new opportunities offered to the emerging sociologies: firstly, the compilation of encyclopaedias of a universal character which also contemplate, as far as possible, contributions relating to themes and authors that do not recur in the better-known literature; secondly, the addition of manuals and companions on a broad international scale dedicated to the sociology of religion; and, finally, the availability of online journals with open access—this novelty makes accessible unusual data and analyses coming from territorial contexts that are usually not taken into consideration, also due to the lack of adequate information and linguistic tools that are at least sufficient for a broad understanding.

As far as the encyclopaedias are concerned, it is worth mentioning, first of all, the valuable work carried out by Adam Possamai and Anthony J. Blasi, editors of The SAGE Encyclopedia of the Sociology of Religion [39], who have broadened the perspective provided by other similar works [40,41], signalling the existence of further tracks for the discipline, including religious radicalisation [42], anti-Semitism [43] and Islamophobia [44]. For the numerous handbooks (and related volumes) published since 2000, reference can be made to those by Malcolm Hamilton [45]; Steven Sharot [46]; Michele Dillon [47]; Phil Zuckerman [48]; Keith A. Roberts [49]; Helen Rose Ebaugh [50]; Ronald Johnstone [51]; James A. Beckford and N. J. Demerath III [52]; Kevin J. Christiano, William H. Swatos and Peter Kivisto [53]; James R. Lewis [54]; George N. Lundskow [55]; Meredith McGuire [56]; Peter B. Clarke [57]; Grace Davie [58]; Roberto Cipriani [59]; Elisabeth Arweck and Mathew Guest [60]; Michael O. Emerson, William A. Mirola and Susanne C. Monahan [61]; Inger Furseth and Pål Repstad [62]; David Yamane [63]; Detlef Pollack, Volkhard Krech, Olaf Müller and Markus Hero [64]; Jayeel Cornelio, François Gauthier, Tuomas Martikainen and Linda Woodhead [65]. Some of these texts have had multiple editions, thus showing a growing interest in the discipline, including the work of Christiano, Swatos and Kivisto; Cipriani; Davie; Johnstone; McGuire; and Roberts.

At the level of journals, two important events took place in the same year: the birth of a widely distributed publication such as Religions, which, since 2010, has selected and published articles of various cultural and scientific disciplinary backgrounds and is freely accessible online. Scrolling through the list of monographic topics covered, one can follow step by step the dynamics of religious phenomenology in various parts of the world. Up to 2015, four issues per year were published, later twelve, a sign of considerable success, given the high number of readers for each article (from a few hundred at least to several thousand in the most interesting cases). The review of Religions includes research articles, reviews, communications and reports on research projects, also with a multidisciplinary slant.

The other initiative also launched in 2010 was the Annual Review of the Sociology of Religion, under the direction of Enzo Pace, Luigi Berzano and Giuseppe Giordan, as if to resume the interrupted series of Internationales Jahrbuch für Religionssoziologie (International Yearbook for the Sociology of Religion), which began in 1965 and ended in 1973. The topics covered by the Annual Review of the Sociology of Religion are, year by year, in order: youth, politics, methods, prayer and spirituality, monasticism, the Internet, atheism, Pentecostals and the body, Catholicism, interreligious dialogue, Chinese religions, religious freedom.

Another remarkable step has been taken by Fenggang Yang of Purdue University, who founded and has been directing, since 2014, the new Review of Religion and Chinese Society, which thus fills a long-standing gap regarding the presence of the sociology of religion in the Asian area.

In the past, the paradigm that religion was dependent on other sociological variables was in force, then the idea that it had its autonomy [66] took over, which in fact can be seen through the theory of rational choice [67] to be made among the different possibilities offered by the persistent socio-religious pluralism [68]. Having also overcome the hypothesis of a so-called strong programme (religion as an independent variable) in the field of sociology of religion [69,70], we have observed a tendency to go beyond the old paradigms, which have proved incapable of explaining and interpreting the complexity and differentiation of religions. David Yamane [63] (pp. 5–6), in particular, has pointed out that the sociology of religion is moving to overcome traditional classical frameworks, addressing itself well beyond Christianity, congregations, beliefs, boundaries, modernity and religion too. This perspective suffers greatly from the peculiarly American contextualisation of the approach, but to some extent, it hits the mark, especially as regards the observation of an unusual enlargement of the discipline, which has gone beyond its specific object. However, Yamane’s observations have a good deal of reliability, if one considers that the sociology of religion is actually frequently limited to the examination of the Christian world, neglects what happens outside the sacred congregational enclosures (temples, churches, mosques, synagogues and so on), overestimates the weight of religious practice, prefers to investigate the local situation without questioning what is happening in the surrounding world, thus denoting a certain provincialism (parochialism). It keeps in mind only one specific form of modernity, whereas in the sociological field, the so-called multiple modernities have long been established [71]. Finally, probably the most significant development concerns religion itself, since there is an increasing tendency to analyse non-religion, i.e., atheism, the so-called nones (non-believers, indifferent, agnostics, non-members, atheists, neutrals) and also here it is another neologism, the so-called dones, i.e., those who have left religion. The increase in nones and dones casts doubt on the very future of religion [72]. Yamane, therefore, proposes to include the subject of both of these last two categories within the general framework of any empirical research, assuming that the aforementioned ways of addressing the religious question are entitled to full citizenship, so to speak, within the sphere of scientific knowledge applied to the religious fact. Ultimately, “whether in the long run the sociology of religion will consolidate around one or a few paradigmatic approaches is uncertain. In the near term, it seems likely to continue to build on past insights while pushing beyond their particular blindnesses” [63] (p. 6). Sexuality and transnationalism too could be mentioned as topics of interest to the discipline. But the developing areas are also others [73,74].

Certainly, there has been a significant increase in scholars and sociological studies on religion in recent decades. The perspectives of analysis have widened—researchers no longer always and only move within their own confessional cultures of reference, but rather push themselves to explore other terrains, other religious forms, unusual ways of attitudes and behaviours of a spiritual nature or similar to it. In other words, the horizons have expanded considerably, making it possible to carry out a comparative analysis that in the past did not have many significant examples of investigation. In other words, the universality of the religious phenomenon has been widely confirmed and has favoured multiple cognitive paths, so much to legitimise the use of a concept that, in the wake of Eisanstadt’s [71] multiple modernities, corresponds to the idea of multiple religiosities; that is, of stratified and articulated religious presences that follow different paths in their phenomenology. This happens in a highly globalised and differentiated context, which shows several typologies, due to the continuous transformations taking place in local societies, which are affected by the impact of transversal trends, able to reach almost every corner of the planet, providing reasons and convictions for the achievement of peculiar identities at an economic and political, cultural and religious level—in Russia as in the United States, in India as in Nigeria, in China as in Brazil and so on. We can, therefore, speak of multiple Islamic modernities [75,76], but also of a multiple Confucianism, typical of East Asia [77].

It is no coincidence that Adam Possamai and Anthony J. Blasi [39] (p. XXVI) cited Eisenstadt and his multiple modernities in the introduction to their The SAGE Encyclopedia of the Sociology of Religion: “today, in globalisation in which religion is less influenced by nations, theories have to adapt themselves to transnational movements and need to reconsider understandings about religion that can no longer be homogeneous. It is indeed more and more difficult today to speak about religion as a universal category. Religion is adaptable and is understood differently within different contexts. Shmuel Eisenstadt’s work on multiple modernities has certainly been key to sociologists of religion to understand that religion can be practiced and understood differently and that the secular sphere that dominates religion can be a restricted or a very fluid one, depending again on the context. We refer to our contemporary period as one of post-secularism, as if religions can now be expressed freely in the public sphere. However, in this context, the prefix ‘post’ is a misnomer. We are still in a secular period even if it is more open to religious beliefs and practices than was the immediate post-1960s period”.

Starting from these considerations on the continuum of secularisation, the editors of the Encyclopaedia immediately opened the discussion on the novelties of the sociology of religion, stressing that “religion has moved to the digital world as well, and as with other types of social research, sociologists of religion are coming to grips with what questions to ask and how to find answers. New approaches, such as big data analysis and online ethnography, are developing in this field of research. This, again, reflects the fact that religion can adapt itself to any new environment and is a persistent phenomenon” [39] (p. XXVI).

A significant development of the theses on secularisation is due to Ulrich Beck, who advanced a new interpretative proposal of the diffusion of religion in the form of the experience of a personal God. Whoever wants to escape hierarchies, dogmas, practices, official beliefs, ideological evaluations and the authoritarianism of structures stabilized over time, builds his own way of being religious (or not religious)—which nevertheless relates to the religiosity proposed by churches and by movements and groups, communities and organizations—and comes to terms with the truths claimed and propagated by the various religious denominations. The option that derives from this, that of a personal God, seems very functional to the individual needs of social actors grappling with multiple and complex, risky and unpredictable problems, which do not always find adequate answers in the recipes proposed by historical, traditional, consolidated religions.

This opens up a scenario that allows people to glimpse a kaleidoscope of variations on the religious theme, not necessarily in conflict with each other or even with the classical models, which nevertheless remain in the background, representing a wide-ranging horizon, where systems of socialization continue to operate with more or less effective results. Even though the latter seem to be diminishing in their scope, they remain influential, even after many years and in key existential circumstances.

The historical precipitating factor in all of this is the return to a sort of polytheism according to the interpretative key of a religious individualism that results in a dual orientation, favouring both the religious solution and its negation, without renouncing the search for transcendence. Death, on the other hand, escapes this kind of consideration and is not included in the list of what is qualified as an “ultimate meaning”, attributed rather to the private, individual world. For Beck, moreover, religious individualization presents itself as a paradox, since religion promotes memory, strengthens ties, fosters collective identities and spreads strong socializing rituals. However, it is from religion itself that individualization takes its cue, insofar as it is founded on the faith of the individual subject and on his or her freedom of choice.

The very promise of eternal life as a form of defeat for physical death is defined by Beck as a disturbing and isolating invention at the same time, a sort of test that leads to eternal life or not, according to the type of life lived. It should be emphasized, however, that the individualization of religion, when and if it leads to the religiosity of the personal God, is not only very different from the individualization in religion, which could also create problems for institutionalized religious forms, unless the latter seek solutions of compromise, adaptation and conciliation.

To make his reading of religious reality even more explicit, Beck proposed ten fundamental theses that are well suited to the theme of diffused religion: first, the diffusion of religious faith is directly proportional to the presence of reasons for uncertainty in existential paths; without going towards the disappearance of religion, a new anarchic mode of religion appears on the horizon, disrespectful of the existing and its usual norms; the individualization of religion is connected to that of society as a whole—families, classes and social groups; institutional images lose relevance, giving way to new words and new symbols; religious practice declines, new forms are amplified that are more fluid and liquid—elusive, as Bauman would say; there is a privatization of religion, but at the same time, it recovers ground in public space (Casanova); the so-called religious truth is transformed both at the institutional and individual level; individualized religion retraces the same symbolic paths of the institutional religious sphere in an evident substantial continuum; the personal God comes at the end of an itinerary that has been institutional, traditional, almost without interruption with the past; the future presents various scenarios, including the aversion to individualized religion, the affirmation of religion in the public sphere (Habermas) and an inclusive perspective of each religion, which relates to other religions, recognizes their contribution and accepts a continuous and open comparison. In this way, religions acquire a universal citizenship that has never been experienced before. The greater diffusion of religions then legitimizes the very expression of “religious universalism” and confirms the tendency towards cosmopolitanism.

Nowadays, the sociology of religion is in very good standing. Think of the work by Charles Taylor [78], A Secular Age, a seminal contribution to the theoretical approach, in terms of an immanent frame (a new concept in the field) through which to express the conditions of belief—that our society is governed by reason. Taylor described how we put ourselves in the world and the idea that we have of it; this is the immanent frame, used to capture and understand the space in which we live. We are in a world where gods and final causes can be eliminated. Within this immanent frame, the relevant thing is this-worldly and self-referential, because the individual is the measure of the good. We are at the beginning of a new age of religious searching. The immanent frame allows for something beyond, but, at the same time, we are oriented towards the closure and the transcendence too. It is no coincidence that the Social Science Research Institute has supported a blog called The Immanent Frame, on secularism, religion and the public sphere.

Another relevant suggestion came from Robert Bellah [79], in the book Religion in Human Evolution: From the Paleolithic to the Axial Age, which took up and broadened his previous analytical perspective [80], considered a cornerstone of the sociology of religion, especially in terms of socio-cultural interpretation of the religious phenomenon. Bellah [81] placed himself at the centre of the debate on the axial age of Jasperian derivation and dialectically rejoined the aforementioned work of Taylor.

Meanwhile, other original topics, to which little attention had been paid in the past, are now being proposed in the scholarly arena, such as the issue of abandonment of one’s religion [82] and the opposite phenomenon of conversions [83], gender diversity [84,85], migration [86], mass media [87,88], developments in new Asian religious movements [89] and the contrast between the secular and religious in urban structures in Asia [90], the problems of violence [91] and the relationship between conspiracy theories and religion [92], connections between ecology and religions [93], those concerning peace and conflict [94], the connections between cities and religion [95,96] and sport and religion [97], monasticism [98], religious diversity [99], chaplaincy and religious diversity in prisons [100,101,102], language [103], the economic aspects of religions [104], legislative issues (especially concerning freedom of religion and human rights) [105,106,107,108,109,110], political issues [111,112,113] and globalisation [114]. The methodology only remains somewhat overshadowed, but there is no shortage of relevant contributions [115].

Amidst the ‘religious turn’ within European philosophy at present, the growth of the study of the phenomenology of religion represents another novelty.

Some atlases on the spread of religions are valuable [116,117]. The same applies to databases [118]. The specific sociologies of religion with a national character have also developed to such an extent that they now deserve special treatment [119]. The attempt of Spickard [120] to offer a different, non-Western view of the sociology of religion should also be mentioned, together with contributions that relate to the Eastern Orthodox Christianity [121,122].

Ultimately, the basic scenario seems to be that of a widespread but uncertain religion [123,124], a perspective already intercepted by Robert Towler in 1984 and, not surprisingly, proposed once again [125]. We are, therefore, dealing with a kaleidoscope of approaches (pp. 1–20 in [74]) that testify to vitality and liveliness that are more pronounced than ever, and which presage further progress in scientific knowledge applied to religions.