Some are saying that the movement of Christianity in China has far outnumbered the members within the Communist party, if one includes the rapid growth of the underground churches.

However, some church scholars in Hong Kong doubt this speculation.

Professor Ying Fuk Tsang, a divinity professor in Hong Kong told Ecumenical News International (ENI) that it is true that Protestants in mainland China have over 14 million members accounted for in the government approved sanctioned churches, which does not include the number of unregistered members of the house churches in China, but the tally for the Communist Party is about 70 million.

And due to the secrecy of the house churches, Ying said "An official data are hard to obtain, it is difficult to make an accurate estimation of the number of home church attendants in the mainland China," reported ENI, a global news agency that reports on ecumenical developments.

Even though, sources have stated that the number of Protestants in the house churches ranges from 70 to 100 million members, Ying, who researches Christianity in China, however, disputes this statistic and states that a more realistic number would be 30 to 40 million members, ENI stated.

What is the definition of membership in the Protestant churches, he said in an interview with ENI, "Should those baptized be considered church members, or should those attending church regularly be regarded as members?"

Another scholar, Anthony Lam Sui-ki, a Catholic researcher of churches in China, has also questioned this claim telling ENI that for Catholic Chinese Christians, the official estimation is 5.3 million members, when researchers have stated the statistic was 12 million, which is still below the Communist Party's estimation of 70 million.

Despite whether the church statistics are accurate, the concern that China has is whether the movement of Christianity will have an effect on the society, ENI reported Ying saying.

He told ENI that "The upsurge of Christianity is really a potential destabilizing factor in the eyes of the Chinese Communist Party," which they believe can potentially spread the concept of a democracy through the Protestant churches.

For instance, among converts are university students and entrepreneurs who, Ying said, are trying to search for "the meaning of life," ENI reported, but "theoretically speaking, those joining the Communist Party have no religious belief…."

Xun Jinzhen, a Christian convert in China, told the Telegraph, "We have very few people who believe in Communism as a faith. So there's an emptiness in their hearts."

The religions that China approves are Buddhism, Islam, Taoism, Protestantism, and Catholicism in a population that is estimated to be over a billion people.