I just interviewed the noted theologian, Harvey Cox, on his new and provocative book, The Future of Faith. I strongly recommend the book.
Cox divides the history of Christianity into three "ages": the Age of Faith (the early Church up to Constantine), the Age of Belief (Constantine to about the mid-20the century), and the new Age of the Spirit (still emerging in the last 50-60 years). At the risk of oversimplifying, he says that the second age, the “Age of Belief,” emphasized subscribing to proper and orthodox teachings. It was pre-occupied with creeds, and statements of belief. Thus, it discovered heresies, inquisitions and other ways to exclude people from the community of “belief.”
The third age, which he says is still in formation, is the Age of the Spirit, which emphasizes – not what people believe – but how they live, how they treat one another, how they experience the divine through spiritual practices or ritual. It is global, and in many ways, interfaith, with practices being borrowed across faith traditions. His examples include a wide range, from the Community of Sant ‘Egidio to liberation theology to global Pentecostalism.