CAN friendship save the Church of England? Would a switch of attention from erotic desire to the love called amity make a difference to the deepening crisis over homosexuality? The bishops have suggested it might.

In recent publications on human sexuality, they have begun asking how friendship might be celebrated, nurtured and given public recognition. A focus on this would have the advantage of taking the matter out of the bedroom, as it were. However, if the tradition provides no easy answers on sexuality, it is ambivalent about friendship too.

The problem reaches back to 376, when the best friend of the young patristic theologian, St Augustine, died. It was a devastating blow that deeply unsettled him. He and his friend had become that rare thing, one soul in two bodies. Now, though, Augustine realised that to hope for too much in friendship is to risk too much too. “What madness, to love a man as something more than human!” he exclaims in his Confessions.

His tragedy cast a shadow that hangs over friendship in the Christian tradition to this day. The ambivalence can be expressed theologically. The love of God is universal and selfless. The love of friends is particular and selfish. So, in the league table of Christian virtues, philia not only scores far less than agape but may even be antithetical to it.

This misgiving makes its presence felt in all sorts of places. Think, for example, of the marriage service. The couple are blessed in their commitment and companionship but not in their friendship. The absence of any reference to friendship seems indicative of a suspicion that it is not up to the ideal of marriage, which is modelled on God’s love, not that of human beings.

But surely it is ridiculous to think of human friendship as a travesty of divine love. Rather, the point is that the deepest kinds of friendship are rare. Aristotle puts it well: “The desire for friendship comes quickly. Friendship does not.” And in fact, this rarity might provide the clue as to how to celebrate it.

Think of the most famous comment on friendship in the New Testament: “A man can have no greater love than to lay down his life for his friends” (John XV, 13). In John’s Gospel, this saying is a comment on the nature of the relationship between Jesus and his disciples: he does not call them servants but friends. Why? Because the friends of Jesus both understand who he is and, critically, are prepared to pay the price of living by that conviction — even to the point of death. So, this is a kind of friendship about which there is nothing ambivalent in its demand.

Or consider the great medieval writer on friendship, Aelred of Rievaulx. His famous work on friendship, Spiritual Friendship, unites its symbolic aspects with the practical and experiential. Thus, for Aelred, the death of a friend does not reveal a misplaced love. Rather, because the love of the deepest friendships lives on in the heart of the surviving friend, the loss can be nothing less than an experience of eternity in the present. As Cicero put it: “Even when he is dead, he is still alive.” Friendship lifts the veil between this world and the next and provides a foretaste of the everlasting love of Heaven, here and now. This is a kind of friendship that is nothing short of sacramental.

Aelred’s theology was the inspiration behind the medieval institution of “sworn brotherhood”, individuals who made a commitment based on friendship which, because it was thought of as a serious religious vow, carried significant social weight. The practice died out in the modern era because it seemed too nebulous in a society that sought strong secular foundations for its institutions of belonging.

Today, though, there is an opportunity for friendship to be recovered. The networked lives of postmodern individuals rely more and more on friendship. If the Church could stop worrying so much about micromanaging people’s sex lives, and turn instead to nurturing the ways in which they love one another, it might redeem itself yet.

Mark Vernon was an Anglican priest. He is the author of The Philosophy of Friendship (Palgrave, £20).