The answer depends on what exactly is meant by “interfaith dialogue.” On one hand, dialogue is good. When a Christian dialogues with someone of a different faith, he or she can often gain greater understanding and useful insight. Learning through dialogue is better than ignorance. Asking questions about what a person believes is a great way to build a bridge. Too many Christians do not really understand the beliefs of those around them and are therefore unable to relate to them and share the gospel effectively.
Where the problem lies in “interfaith dialogue” is that, to most people, interfaith dialogue starts with the premise that no religion is “superior” and that all faiths are equal. Evangelization or proselytizing is inherently arrogant and disrespectful, since all roads lead to God. To many, interfaith dialogue involves various religious adherents looking for common ground that will give them a foothold for combating societal and human ills together. The sole purpose of such dialogue is to unite enough to attack the “real” problems facing humanity, which have to do with human relationships and human suffering.
Some nominal Christians embrace the compromise of interfaith dialogue because they think that the central message of Christianity is love. These people see all other doctrinal issues as unimportant as long as a person lives a good life and is attempting to help others. What does it matter what minor details people believe about God or the resurrection or the Bible, as long as they agree to love each other and work together to solve humanity’s most pressing problems? What does it matter if a person does not believe in Jesus, as long as he or she lives the kind of life that Jesus lived?
For biblical Christians, however, the primary problem is not horizontal (man to man) but vertical (man to God). While sin involves mistreatment of other people and interpersonal alienation, the greatest problem is that sin alienates us from God and puts us under His righteous condemnation. (This is the premise that promoters of interfaith dialogue deny.) Solving the sin problem is of primary importance. Jesus claimed to be the ONLY solution. “I am the way, the truth and the life. No one comes to the Father except through Me” (John 14:6).
At one interfaith memorial service after the attacks of September 11, 2001, several adherents of different “faiths” (religions) were involved. The “real problem” was identified as religious extremism and violence and human suffering. One person read a passage of comfort from the Bible: “For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers, neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God” (Romans 8:38–39). The passage, as read, fit well within the interfaith environment. However, the passage, as read, was out of context, because the last few words of verse 39 were omitted. The promise is that nothing can separate us from the love of God “which is in Christ Jesus our Lord.” Those last few words, as well as the whole context of the chapter (which begins, “There is therefore now no condemnation for those who are in Christ Jesus”) is off limits in interfaith dialogue. The truth of Christ divides (see Matthew 10:34).
In the final analysis, Christians should be involved in dialogue with non-Christians to understand what other people believe and to build bridges. The goal is to share the gospel effectively. Addressing a humanitarian problem is also good, but humanitarian efforts should always be done with a view to earning a hearing for the gospel. The mission of the Christian, in obedience to Christ, is to make disciples (Matthew 28:19). If the rules of the dialogue forbid pressing the claims of Christ, then the Christian should opt out. In most cases, this is exactly the situation found in formal interfaith dialogue.