Although China is officially an atheist country, its Protestant population is likely to swell to 160 million by 2025, according to a religion expert, who says not many are prepared for "this dramatic change."
"By my calculations China is destined to become the largest Christian country in the world very soon," Fenggang Yang, a professor of sociology at Purdue University, told The Telegraph.
"It is going to be less than a generation. Not many people are prepared for this dramatic change," adds Yang, author of Religion in China: Survival and Revival under Communist Rule.
Yang predicts that China, which had over 58 million Protestants in 2010 according to the Pew Research Center's Forum on Religion and Public Life, will have around 160 million by 2025. This would mean China will likely be ahead even of the United States, which had about 159 million Protestants in 2010.
Yang went on to say that China's total Christian population, including Catholics, would be over 247 million by 2030 and thus become the largest Christian congregation in the world. "Mao thought he could eliminate religion. He thought he had accomplished this. It's ironic – they didn't. They actually failed completely," he said.
When China's communists came to power in 1949, they expelled Christian missionaries while allowing churches to function under the government's control. Chinese Christians faced severe persecution during the Cultural Revolution of the 1960s and the 1970s under Mao, who saw religion as "poison." However, Christianity continued to grow like fire.
Churches are allowed to function since 1979 but only as long as they register with the government and thereby come under its control.
"They want the pastor to preach in a Communist way. They want to train people to practice in a Communist way," a house-church preacher told the British daily. "They do not trust the church, but they have to tolerate or accept it because the growth is there. The number of Christians is growing – they cannot fight it. They do not want the 70 million Christians to be their enemy."
However, hundreds of thousands of unofficial house churches, largely indigenous, exist all across the country. Evangelism is allowed, but only in state-approved religious venues and private settings.
Persecution of Christians continues with unofficial churches facing its brunt. The World Watch List ranks China as the 37th worst country in the world for Christian persecution.
With many Christians still not revealing their religious identity, the exact number of Christians in China is not known.
According to a recent study, online searches for the words "Christian Congregation" and "Jesus" far outnumbered those for "The Communist Party" and "Xi Jinping," China's president.