First, under persecution, the early church and the Chinese church required commitment and authenticity. That people can be killed for believing in Jesus would require something more wholehearted out of a person than what is usually required of Western Christians nowdays (despite the fact that being mocked is genuine persecution). The sheer authenticity and commitment of Christians was probably quite attractive and convincing to observers, who were living in a spiritual void in both situations.

Second, in ancient Rome and in 20th century China, Christianity didn’t come with familiar and tired cultural baggage. People in Rome couldn’t look back on centuries’ of mistakes made by Christians and use that as an excuse to reject the Church. In China, surely they knew some Western history, but for them it might not have been as visceral. Roman and Chinese Christians also didn’t see widespread hypocrisy that exists when Christianity (or any religion or ideology) is a prominent cultural phenomenon, whereas they probably did see widespread hypocrisy in the dominant religions and ideologies of their time and place. In general, Christianity couldn’t be used as a means for guileful people to gain social standing. That in itself cuts back a lot of hypocrisy. Not to mention that Christianity also had the allure of the new and the forbidden.

Third, and most importantly, without Bibles or institutions as we are accustomed to having them, the churches and individual Christians had to rely on the presence and power of the Holy Spirit, which, to put it simply, is the life, power and unity of the Church. Life is contagious. Where the Spirit is unbridled, miracles are normal, hearts are changed and minds are renewed. Miracles are a powerful witness. People who are genuinely renewed to christlikeness and deep, authoritative knowledge of God are an even more powerful witness. Nowadays, in the West, Christians have so much Bible and Bible parsing that they often neglect the eternal Spirit of God who literally is our eternal life and our source of experiential, nonanalytical knowledge of God.

I would also echo the words of Anna & Jeff above, when they mention the importance of the verbally oriented tradition. The very words of God hidden deep in believers’ hearts is another powerful witness.

A typical recent conversion story there was that someone was converted after a family member converted. At first they disapproved, but gradually were won over.

The first family member usually attributed the conversion to a healing experience. They had a significant illness, consulted with Western and Chinese doctors, maybe saw a Qigong healer, and prayed to ancestors or other gods to no avail, then they met a Christian who urged them to pray to Jesus (or prayed for them), they were healed, and they became Christians.

The urban situation in China is quite different, I think. I have no idea how that would compare to a typical conversion in ancient Rome.

Other religions do not have a very strong following in north China where I have lived. People do seem to be thirsting for something to believe in.

To put it in more theological terms, when the Christian community embraces and cares for people, they experience fellowship with the risen Christ. To be cared for by the Church, after all, is to experience the care of Jesus who very closely identifies with the Community.

As the first commenter pointed out, persecution lends a strong cohesion to the group. I would argue that one of the major differences between the pre- and post-Constantinan churches is the degree of meaningful ties to the new community, and the necessity of cutting ties to the world, the Roman civic community.

When folks in the Roman Empire became Christians, generally speaking, they had to give up certain trades, particular behaviors, and embrace a new story that would form the basis of their interactions in society. And it’s not for nothing that these Christians were called “atheists” – withdrawal from any and all participation in the civic cult was a concrete rejection of society’s Roman order. The Christian Eucharist was (among many other things, of course) a subversive counter-imagining of how social relationships fit together.

I think this article in Touchstone by Mike Aquilina a direct and fascinating answer to your question.

Today we might call it ‘viral marketing’.

1.) Persecution forces them to find shelter in each other. The predominate culture has orphaned the Christians socially and politically for choosing the Jesus way. Community is formed for survival as well as for growing in the faith. This is also very attractive to outsiders in an otherwise atomized (Communist/despotic) society where anyone could be deemed the next enemy of the state.

2.) The lack of Scripture (or the ability to read)creates the need for memorization and a verbally-oriented tradition. Rehearsing the stories, the songs, the psalms helps in personal growth. When imprisonment, torture, and isolation comes, the believers can feed themselves from the wealth of the Word within. Chinese pastors make circuts between meetings with a certain set of scripture and songs memorized to share with each cell. The group learns it and repeat it until the next time the pastor returns.

3.) Persecution also refines those who are gifted in leadership. Its fairly easy to pick out those who will stay true to the flock when the heat is on. Elder leaders focus on intense discipling of young potentials because they don’t know how long until the soldiers come for them.

4.) Tying into the verbal-oriented culture, the Chinese/ancient world did not have the convenience of Christian radio/tv/mass print media. In order to learn of Christ, you pretty much have to be in physical contact with other Christians. No lazy contributions to international media ministries (unless it is an apostle, in which case, you’ve probably met them already). China and the ancient world also had a strong family ethos. If you are shunned from your blood relatives, your faith community is it.

We might be wrong so you can reprove/instruct us.

Anna & Jeff