Religious belief sustains society by causing a person to act more virtuously than he needs to in order to placate society at large, since he compares his behavior to a standard which exceeds the morality of society.If we get our moral standard from society we are unlikely to ever behave better than society. But society is just the average of all of us. So if nobody actually behaves better than the average then the average is going to go down over time. We will all try and be as good as the next man. We will all be about 90% successful. But it will add up to a steady decline in morality. It is not sustainable. It leads to anarchy.
This does not mean religion is true. It just means that if it isn't we are in a real quandary. We can try and push a religion that is not true. That is hardly sustainable. We can try and find transcendent moral principles outside religion complete with strong motivations for following such principles. But that is just manufacturing a religion. Essentially it means that as a society we are in trouble. We are in a moral death spiral. We need a savior.
He then turns to the question of whether evangelicalism is sustainable. Whether it can pass the faith on to new generations without declining each time. He sees a big problem there too. He sees the issue as a degrading of doctrine. Traditional and biblical Christianity has been replaced by Moralistic Therapeutic Deism.This is just secularism with religious language but research shows it is what many church-going young actually people believe.
Then he looks at fundamentalists. They have maintained doctrinal purity but at the expense of much division and a lot of debates over small matters of doctrine. He does not see them as sustainable either.
So who does he see as sustainable? Coptic Christian immigrants in Australia. He saw them as maintaining both unity and doctrinal integrity even among their youth. Something no protestant group was able to do. He is a bit confused as to why such a group might succeed where others have failed. He identifies a few things. Tradition is one. He does not mention liturgy and sacraments. I would put them pretty high.
He seems to be suggesting that evangelicals steal a few ideas from the Coptics. That they are authentic in a way most churches today miss.
Young people are perhaps always preoccupied with authenticity, perceiving a general lack of it in themselves and in society. An authentic and true connection to Jesus Christ, then, should be the number one priority of those involved in youth ministry. And I don’t think this means having more altar calls, Switchfoot concerts, or endless guilt trips about frequency of personal devotions. I believe we need to teach children, teenagers, and young adults how to eat Christ as part of a worshipping Body. This can be accomplished with or without a praise band, cool graphics, or edgy haircuts. These things are mistaken for relevance, but to the main issue they are completely irrelevant. The Body of Christ is the central and eternally relevant element of a sustainable Christian religion, because by this He himself sustains the church.So the most important thing is for the church to be the Body of Christ. But that is not something we can be on demand. It is something we are by grace. So we should not look to manufacture relevance. We should think about what being the Body of Christ really means. Maybe ask the Coptic Christians. They would talk about apostolic succession and sacred tradition and the real presence of Christ in the Eucharist. The kinds of things that evangelicals can't just incorporate into their programs. These are things that require letting your whole idea of church die and embracing a visible church that is the Body of Christ. That is the true sustainable religion. All the houses built on sand will fall. The one built on the rock will survive.