Bible outreach in China today is a world away from the terror of the Cultural Revolution. During those decades, Bibles were confiscated and churches were shut down. But since the churches have reopened and been allowed to distribute Scripture, the Bible has gone from being an underground book to a bestseller.

Religious activity, particularly by foreign organisations, is still heavily restricted in China, and we've taken care to cultivate a relationship with the authorities that over the years has borne fruit. Since 1987, when Bible Society was invited to set up Amity Press in Nanjing, 90 million Bibles have been printed for distribution in China. (As the largest Bible factory on earth, Amity has also produced 140 million copies in various languages for distribution around the world.)

Having been made available through authorised vendors, the open Bible has driven the amazing growth of the Chinese Church. Bible Society's former mission leader in China, Kua Wee Seng, says: "The Church in China is experiencing a revival because the word of God is like wood in the fire."

The living word has filled to bursting China's reopened churches, overstretching the very limited availability of ministers. On average, more than six and a half thousand Christians will be served by a single ordained pastor, mostly in less affluent areas, not at all representative of China's new wealth.

The leadership gap is filled by dedicated volunteers as people step up to serve the congregations they're part of without payment and often without training – and sometimes from backgrounds that in worldly terms look extremely unpromising.

For instance in Yunnan, among China's Wa speakers, Bao* leads a church with a hundred members who are new believers. Bao is a former drug addict, and found release from his addiction through an encounter with Scripture in the Wa language. Some years ago he started a community centre that supports 800 people a year who suffer addiction, reaching out to others in the same situation he once was himself. He provided medicine, took people for tests and visited them in hospital.

For others, ministry brings different challenges – like finance. "Seeing that I spend so much time in church," says Pu Zhidui, a 50-year-old lay leader, "my non-Christian friends had actually asked me if I received any monetary support as a preacher!" He doesn't, but that not stopping.

Pu visits eight churches, high in the mountains of China's impoverished Yunnan province. In his county, he's one of 67 lay preachers serving 80,000 believers. Although unfinanced, Pu is at least trained, having studied at Fugong Bible School (where he vividly recalls reading the Bible cover to cover by candlelight).

This is far from normal in China's churches. Wang Zhengxiang, for example, is a former miner and 'uneducated' by his own admission. Bible college for him was the year he spent in a prison cell with a Bible and a hymn book. A widower at 25, and seriously injured in a mining accident, Wang took hold of a half-remembered childhood religion as his last resort. He became a lay preacher because he couldn't stop telling people about the difference God has made for him.

"I took every opportunity to share God's goodness in my life," Wang says. "Some folks were encouraged by my sharing and even pointed out that the Lord had shielded and protected me despite the challenges I have experienced."

Irrepressible, and certainly an asset to any of the local churches he pops up in, Wang has been provided with Bible study books through the generosity of Bible Society supporters. (Our positive relationship with the Chinese authorities has created the unique opportunity for us to provide training support to lay preachers at the invitation of churches in China.)

Joshua 25.14 is a favourite of Wang's. "I want to serve God all my days," he says, effectively speaking for many of his colleagues among China's tens of millions of Christians.

Sun Liujun is similarly enthusiastic, having served his congregation since 2002, but he's come to preaching from a completely different background. Liujun ran a successful textile business, building relationships with clients and suppliers through lavish parties characterised by heavy drinking with the occasional brawl. He wanted a way out, and the only one that worked came through his mother's invitation to accompany her to church. Liujun was literate in a congregation where many lacked this skill, so he'd volunteer to read the Bible aloud and copy out verses for believers to memorise. The power of the words changed him, and they're driving him forward today as a lay preacher.

Volunteers like Liujun support an ordained pastorate full of people who left behind more lucrative options. Thirty-six-year-old seminary graduate Gao Yong was advised against the ministry by his family. "My child was just six months old,' he said. 'I've worked in a company and I was even my own boss when I started a business, but all these jobs did not bring lasting satisfaction. I watched with envy pastors who are in the business of transforming lives."

Wang Zheng, 46, also made a mid-life career switch a few years ago. He used to work in the music industry, which although similarly unstable has potential to be much more lucrative. He gave up that world to enrol at Huadong Theological Seminary in Shanghai. "Since becoming a believer, I've been convinced that I should use my talents and gifting to serve God," he says.

Han Xue graduated at just 22, having decided on the ministry back in high school. "The faith of my grandmother and mother has had a great influence on me," she said. "If I were to choose again, I would still serve God full-time."

The leadership situation in China is a perfect illustration of Jesus' words in Matthew 9.37, "The harvest is plentiful but the workers are few." When each pastor or preacher has to minister to so many thousands of believers, the load on them is immense. With more to share it, the potential for growth in the Chinese Church would be even greater. In the meantime, a small band of harvesters – too small – work faithfully to preach the gospel and teach God's word, often lacking the resources that would make them more effective and facing challenges that would defeat most people. But rather than just calling the equipped, God is equipping the called, with Spirit-inspired faith and devotion – and the Church continues to grow. The question remains, though: how much more could these workers achieve with the training, funding and other resources taken for granted in so many other countries?

Bible Society is in a unique position to resource Chinese pastors and preachers with training and study materials, and to support outreach to minority-language communities in China. Find out more on the Bible Society website.

*Although we have approval to work with China's official churches, in a context of religious restrictions, we still take care to change the names of people whose stories we tell, including in this article.

James Howard-Smith is a writer for Bible Society.