Or is it worth running the risk in order to unite the world's religions in the cause of peace?

Bishop Bernard Fellay, superior general of the Society of St Pius X (SSPX), has said that he is “deeply indignant” at the Pope’s decision to hold another inter-religious gathering at Assisi.

Bishop Fellay is not alone in viewing these gatherings with suspicion. Benedict XVI himself, as Cardinal Ratzinger, chose to miss the first one in 1986. He said later that the sight of Jews, Christians, Muslims, Buddhists, Sikhs, Hindus and others praying together could give “the false impression of common ground that does not exist in reality”. But he insisted on the possibility of “multi-religious prayer”, in which members of different religions prayed at the same time for the same intention without praying together. And he did attend the second Assisi gathering in 2002.

Yet even if different religious leaders are not, strictly speaking, “praying together”, it still looks like they are: the impression is given that all religions are equally valid, that they believe in the same God.

On the other hand, to unite the world’s religions in the cause of peace is a crucial and pressing task – one that would be especially appreciated by Christians in the Middle East.

So, do inter-religious gatherings sow confusion among the faithful? Or is bringing the world’s religions closer together worth that risk?