Religious diversity is often portrayed as a feature of modern life, and it is regarded as a sign of progress in knowledge and character to enjoy the variety. Somehow it is thought that the more a person is exposed to multiple opinions, the more he should be regarded as ignorant and arrogant if he continues to assert his own as the only truth. But one does not follow from the other. Everything depends on the nature of these opinions. It may be that the more a person is exposed to them, the more he perceives the wisdom of his own position and the folly of alternatives.

In any case, religious diversity is not new. The apostles did not have to travel to China, India, or the New World to be exposed to other religions and philosophies. They lived at a time when Greek and Roman cultures were prominent, and the history of their own people was marked by idolatry. People have been exposed to many opinions and cultures since Genesis. The prophets and apostles understood religious diversity, but they rejected it.

This must be one of the things that define an authentic Christianity. There is no true Christian faith, no true commitment to Christ, without a rejection of religious diversity. A woman cannot say, “I swear to remain faithful to my husband, but I plan to be with many men.” No, if she remains faithful to one, she must reject all others. A monotheist cannot say, “I believe that there is one God, but I appreciate the viewpoint of those who believe that there are many gods.” No, if he believes that there is one God, then he must declare that all polytheists are wrong. Likewise, a Christian must be against all non-Christian religions, or he cannot be a true Christian. He must deny that religious diversity is an ideal, and he must deny that religious tolerance is a virtue.

God has defined true religion in a specific and narrow manner. Peter says that the way to salvation is in Jesus, who is called Christ, the prophesied Messiah. He refers to the one from Nazareth, the one whom the Jews crucified, who died, but whom God raised from the dead. Salvation comes through this person, and no one else, because there is no other name given to men by which they must be saved. All this is said in our very short text, and reinforced throughout the Old and New Testaments, with the prophets as forerunners who denounced all non-biblical religions.

This matter is of such seriousness that, I would insist, all those who show the slightest sympathy for non-Christian religions must be tried before church courts and shamed before the covenant community. This is especially urgent if they are leaders and professors. They must be immediately expelled from church and seminary premises, and cut off from all association with believers. Now, this is stated only as a matter of principle, since I have no expectation that it will be carried out in the near future. I have no confidence that Christians have the courage and zealousness to enforce the word of God. Christians are not strong enough, not faithful enough, and they do not care about the Lord Jesus enough. They do not even like him very much.

So religious diversity flourishes, along with tolerance and disobedience. Nevertheless, while religious diversity is not a good thing in itself, in God’s providence it could serve to benefit an unfaithful church. Religious diversity flourishes because the church is weak, because it is unsound in doctrine and practice. These are the same flaws that allow false believers to remain in our congregations. But because religious diversity flourishes, and because tolerance is considered a virtue, this same cultural trend that has been enabled by the church’s disobedience also helps to expose and draw away some of the false believers in our congregations.

In my judgment, and I am not alone in this, false believers constitute a majority of church members today, most likely a very large majority. For this same reason, non-Christians are in control of church assets, creeds, policies, and programs. This is vividly illustrated by the number of denominations that have now voted to permit homosexuals to become ordained ministers. Those who contributed to this are non-Christians, including those who campaigned and voted for the change, and those who spoke for it and approved it. The church has long been a comfortable place for unbelievers due to its weak preaching and spineless policies. But now we can know who these unbelievers are – we can know many of them by name.

Religious diversity provides a distraction from truth, and a temptation to those whose hearts do not cling to the Lord. A false believer is more likely to stay where he is and go along with others around him if he sees no other option. But diversity helps to expose those who are not true in their faith. At a time when Christians are weak and unfaithful, diversity helps to slow a quiet takeover of all of Christendom by unbelievers. And it also compels true believers to remain alert, to become decisive in practice, precise in doctrine, and vigilant in prayer and ministry.

Ask a person what he thinks about religious diversity, and you will know his heart. Ask a preacher or theologian if he thinks there is anything we can learn from non-Christian religions, and you will know whether to welcome him into your home, or to throw him out on to the street. Ask a church if it insists that faith in Jesus Christ of Nazareth is the only way to salvation, the only way to escape endless pain and fire, and you will know whether it is a church of God or a synagogue of Satan. Thus in our weakness, God turns a weapon of the devil into a tool our hands, lest his chosen people be destroyed and wiped out.