IN RECENT days, a group of 11 distinguished veterans of the Catholic priesthood in the German city of Cologne, a stronghold of the church, issued an open letter to mark the 50th anniversary of their ordination. Did they use the occasion to ponder aloud the mysteries of their creed, or the wisdom gained in decades of service to the faithful? No. They simply issued a heart-felt cry of pain over their own solitude, a condition they would not wish on future cohorts of clerics. Imploring the pope to allow priests to marry, they wrote:

What moves us is the experience of loneliness. As elderly people who are unmarried because our office required this from us, we feel it vividly on some days after 50 years in the job. We agreed to this [form of] clerical life because of our job, we did not choose it.

The isolation experienced by elderly clerics, especially in wealthy, liberal societies, is one symptom of a crisis in the Catholic priesthood. They were ordained at a time when their status as men dedicated to the church was understood and revered, sometimes to an unhealthy degree. In that era, priests could look forward an old age in which the respect and support of the faithful might compensate to some degree for the absence of any life-partner. With the standing (and finances) of the clergy damaged, in many countries, by child-abuse scandals and shabby attempts to cover them up, the twilight years are a harder prospect than ever for priests on their own, even those who have led exemplary lives. Small wonder that fewer and fewer young men want to walk the same stony path.

As measured by the number of faithful, global Catholicism is faring decently. The flock is still growing in the developing world and migration from poor countries is reinvigorating tired congregations in the West. But the priesthood, with its hard calling of celibacy, is in freefall in many places. In America, the number of Catholics connected to a parish has risen over the past half-century from 46m to 67m, while the number of priests has fallen from 59,000 to 38,000. In France, about 800 priests die every year while 100 are ordained. Priest numbers there have fallen from 29,000 in 1995 to about 15,000. On present trends they may stabilise at less than 6,000.

The result is that many jobs once done by priests, like taking funerals or ministering to the sick, are now done by lay-people or by deacons who may be married. But certain functions, including the consecration of bread and wine which is Christianity’s most important rite, can only be performed by a priest.

And in Latin America, the paucity of clerics is one factor driving the devout to switch from Catholicism to Pentecostalism and other non-conformist creeds, where there are plenty of pastors to serve their needs. Leonardo Boff, the left-wing Brazilian theologian who left the priesthood in 1992 and then married, has described as “catastrophic” a situation where 18,000 priests in his country serve 140m Catholics. He predicts that Pope Francis will soon be obliged to allow married priests, on an experimental basis, in Brazil alone.

Austen Ivereigh, a biographer of the pope, has noted that next year a synod of bishops will consider the crisis in priestly vocations. But Pope Francis is already coping with high-level resistance to the outcome of the previous synod, simply because it cautiously held out the prospect that people who divorce and remarry might be readmitted to holy communion. In some ways, the question of allowing priests to wed should be easier. As is often pointed out, the Catholic church does already have a small minority of married priests, including Eastern-rite Catholics and former Anglican clerics. But the decision-makers are invested in the status quo; the current bishop of Cologne is among those who think the celibacy rule should remain.