“HOW can we face God if we collect taxes from religious men?” asked the deputy speaker of South Korea’s national assembly. The Christian Council of Korea, the country’s largest Protestant lobby, threatened to launch campaigns at election time against legislators who supported the bill. Clerical pressure has for decades stalled a vote on a tax. But on December 2nd MPs agreed to impose one on the income of religious leaders from 2018.

South Korea is the only advanced country that exempts its clergy from all taxation. Still, many Buddhist monks and Protestant pastors pay dues voluntarily on their personal incomes; all Catholic priests have done so since 1994. In September the Presbyterians said that they would join them. Priests who support the new tax say it is only fair: everyone is doing God’s work, whether reverend or farmer. But others scorn the idea. They say taxes reduce the godly work of the clergy to mere labour.

The Church Finance Accountability Network, a voluntary group which advises churches on managing their budgets, says that pastors should set an example. There is a widespread belief that some churches are averse to tax because they do not want closer scrutiny of the huge sums that cross their collection plates. Last week the National Tax Service said it had discovered 63 organisations that had issued receipts for fictitious donations (and had received kickbacks from the tax-dodgers). Almost all of them were religious groups. In a recent poll of 1,000 South Koreans by the Christian Ethics Movement, a local reformist body, only two in ten thought Protestantism was trustworthy. Almost a quarter of those who did not think so said churches needed to make their accounts more open.

The capital, Seoul, is home to 17 mega-churches with over 2,000 members each. Ministers manage them like businesses—and sometimes live like tycoons. Yoido Full Gospel Church, founded by Cho Yong-gi, has interests in a national daily and a university (with 830,000 worshippers, it is the world’s largest Christian congregation). Last year Mr Cho was convicted of tax evasion and of embezzling 13 billion won ($12m) in church funds. In 2013 Sarang Community Church reopened in a gleaming glass structure that cost 300 billion won to build in the ritzy district of Gangnam. Retiring clerics often receive a car or a flat. Mr Cho left with a tidy 20 billion won.

Exuberance has long been a hallmark of South Korea’s brand of Pentecostalism. It subscribes to a gospel of success, not one of sacrifice, says Kim Sung-gun of Seowon University. Many worshippers believe that their devotion helped South Korea prosper and that their riches are a sign of God’s blessing. At a recent service, a preacher at Yoido prayed that the country might attain a GDP-per-person of $40,000, echoing a plan by President Park Geun-hye for 2017.

But Pentecostalism is losing some of its appeal. Koreans are increasingly drawn to Catholicism, which they regard as more humble and serious. According to the latest census, the number of Catholics grew by three-quarters in the decade to 2005, to make up 11% of the population. Protestants were 18%. Chong Chae-yong of Kangnam University says South Koreans “consume the image of a church rather than its doctrine”. Paying tax may help fill pews.