John Calvin identified two marks of the true church: “the word of God purely preached and heard, and the pure administration of the sacraments.”
The only legitimate reason to take the church underground, then, is to overcome any hindrance to the word of God being purely preached and heard, and the sacraments purely administered.
- When the government determines who may preach, what may be preached, or where preaching may take place, the church is obligated to operate underground rather than accommodate the restrictions.
- When the government or the general public restrain the free hearing of the gospel, the church is obligated to go underground rather than accommodate the restrictions.
- When the pure administration of the sacraments is impaired, the church is obligated to go underground rather than accommodate the restrictions.
Let us consider an increasingly common example. Suppose a government permits the church “freedom of religion”: they may preach and hear the word and participate in the sacraments, but only inside buildings officially registered with the government. Is the church obligated to go underground?
Yes, the church is obligated to go underground because in such a situation the word and the sacraments are no longer able to be purely preached, heard, or administered almost anywhere in that society. In such a situation the church goes underground not so it can preach and hear and participate in the sacraments only in a small secret cave or in a clearing in the middle of a forest. (This is the stereotype of the underground church.) Instead, it goes underground so the word and the sacraments may not be bound, in faithfulness to the truth of 2 Timothy 2:9. (For the Christian, truth is defined by the scripture, not the government or the general public. The scripture says that the word is not bound, and the church believes this even when the government insists otherwise.) Since the word and sacraments are not bound, then the Lord will lead the church to many places outside the church building where he desires that these means of grace be shared.
Let us consider another example. Suppose a government enacts laws criminalizing statements against homosexuality in public places or media, including Christian teaching that homosexuality is a sin. The government assures the church it can still do whatever it wants in its own building. Is the church obligated to go underground?
Yes, the church is obligated to go underground because once again there is an attempt to bind the word. The church is the servant of the word and the sacraments; the word and the sacraments are not servants of the church. This means that the church must serve the word wherever the Lord wants the word to be heard. The Lord does not respect the world’s boundaries of where, when, and by whom he may send his word, nor to whom he may send it. He has overcome the world, not simply acquired real estate in it.
The church in the free world, however, is prone to accept restrictions like these from the government, rather than go underground. The church says, “Our congregation is still able to preach and hear the word and administer the sacraments; it is not necessary for us to go underground.” But this attitude makes the church Lord, and the Lord, servant. The church in this case is like the fool in the Lord’s parable who says, “I’ll say to myself, ‘You have plenty of grain laid up for many years’”:
But God said to him, “You fool! This very night your life will be demanded from you. Then who will get what you have prepared for yourself?” This is how it will be with whoever stores up things for themselves but is not rich toward God.
The word and the sacraments are not to be stored up for the church in the church by the church. The church can no more bind the word and the sacraments than the world can. They are not bound. The church is obligated to follow them and serve them wherever the will of the wind pleases to take them.
Action Steps for Church Planters:
- Are you planting an underground church because you are against something in society or in the existing church? If so, cease immediately and repent; no church may be planted because the planter is “for” something or “against” something else. The church is the servant of the word and the sacraments, not their master.
- Are you physically and spiritually prepared to die for the enemies of the gospel? If not, you will not be able to keep the main thing the main thing in the underground church. First, prepare to preach, pray, or die anywhere at a moment’s notice, and only then will you be ready to plant the underground church.
Action Steps for Existing Churches:
- Study when, how, and why existing churches in Germany went underground. Study especially the Confessing Church’s Barmen Declaration and add it to your church’s foundational documents and creeds for memorization and study.
- Ask yourself, “Can the word of God be purely preached and heard, and the sacraments purely administered everywhere in Korea?” If not, where not and why not?
- Is the main thing still the main thing at your church? Or are sermons becoming shorter and shorter and sacraments becoming less and less frequently administered so that other, more popular things may become main things? When the congregation can only endure 20 minutes of sound biblical preaching, should the pastor accommodate that or preach as long as necessary for the fullness of the gospel to be heard, no matter how unpopular that may be with church members and visitors?
- The rich young ruler (Mark 10:17-27) was prepared to obey the word within his own domain, but he was not prepared to abandon his own domain and follow the word wherever the wind was pleased to take it. Scripture says this is because “he was one who owned much property”. As the government and the general public begin to try to bind the word in Korea, are you prepared to sell all your church has in order to go underground so that you can accompany the word wherever it wants to go? The Lord says that the man with big barns was not wise to be tearing them down in order to build bigger barns at such a time. What does wisdom dictate that you do now to be able to follow the word and the sacraments into the areas where the Korean government and general public are likely to try to bind them?
(Excerpted from Pastor Foley's book, Planting the Underground Church. To order a print or electronic copy of the bilingual Korean/English edition, visit Amazon or click here to visit the bookstore page on our website.)
 Eric J. Titus, “Calvin’s Marks of the Church: A Call for Recovery,” UDK:265.1:265.3 Professional paper, 2011, p. 114.
 Luke 12:19-21, NIV.
 See John 3:8, NIV.
 See http://www.sacred-texts.com/chr/barmen.htm.