Many members of the church of Christ have been asked this question before in some form, although often it is less of a question and more of an accusation: "You believe that only members of the church of Christ will go to heaven! How dare you hold such a judgmental belief!"
If you've ever been in a situation like this, knowing the best way to respond can be quite a challenge. Colossians 4:6 instructs us - "Let your speech always be with grace, seasoned with salt, that you may know how you ought to answer each one." It is good for us to reflect upon situations like this so we'll know how to reply in a gracious way with God's truth at any time.
When I find myself in a controversial conversation like this, I try to refrain from giving direct answers. My desire is not to be evasive or non-committal. But, to initially answer with a "yes" or a "no" is typically not in the best interest of the inquirer for a complex topic. It might kill the dialogue on the spot and extinguish any opportunity to explore the matter in-depth with them. Instead, I will try to guide the dialogue to the Scriptures by using questions. God's word is the authority, not my opinion nor any other person's opinion for that matter.
For example, if I was accused of believing that "only members of the church of Christ go to heaven", I might calmly reply with this question: "Whom do you believe will go to heaven--and why?" This shifts the responsibility back to him to first state his view on the matter and then explain why he holds that view. Hopefully, he will bring up certain passages from God's word as a rationale for his position. If no reference to God's word is made in his answer, I might reply with a sincere question geared in that direction: "Where can I find this view you have suggested in Scripture?"
Once he brings up a specific Scripture (or perhaps several), that provides a place to start. I will open up the Bible and study with him, guiding the conversation by using questions where possible (instead of assertions). Getting the conversation grounded in the Bible as the authority is of utmost importance. The answer to any important question will be found in Scripture--either explicitly or implicitly--for God has given us everything we need to be thoroughly equipped as His workers (cf. II Tim. 2:15; 3:16,17). For him to state an opinion and for me to state mine will not maximize the opportunity for good; God's word needs to be opened.
If he struggles to cite a verse for his position, I would kindly suggest beginning with Hebrews 11:6 - "But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him." Then I would ask these questions: "What will happen to those who do not have faith? Will they go to heaven?" Typically one in this situation will affirm that those who don't have faith can't please God and, since they aren't seeking Him, He will not reward them (especially not with a home in heaven). Thus, he will likely not hesitate to declare that those who are non-religious or atheistic will not live eternally with God. Faith in God is a "must"! This is a significant (and correct) admission, and it establishes common ground (which is wise to pursue in dialogue).
This enables me to proceed by saying: "You're absolutely right. One cannot go to heaven without faith in God. But, what do you say to those who think you're judgmental on this point?" Hopefully he will reply by emphasizing that he isn't the judge, God is, and God makes the rules (which is exactly right). One can go a little further with these questions: "Does it bother you to say that 'only those with faith in God can go to heaven'? Does it bother you that this will condemn hundreds of millions of atheists and non-religious folks to hell?" Likely he will admit that it does bother him to think of so many being lost, but this is what God's word says; God is the judge.
Then I will transition to other Scriptures and use the same type of questions. In John 14:6 Jesus declared - "I am the way, the truth, and the life. No one comes to the Father except through Me." He also stated in John 8:24 - "If you do not believe that I am He [the Messiah & Savior, -SRB], you will die in your sins." Acts 4:12 teaches - "Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved."
The above Scriptures, coupled with these questions, will lead anyone with a respect for the Bible to the conclusion that many in our world are going to be lost. This sad reality is precisely what Jesus taught in Matthew 7:13,14 - "Enter by the narrow gate; for wide is the gate and broad is the way that leads to destruction, and there are many who go in by it. Because narrow is the gate and difficult is the way which leads to life, and there are few who find it." To affirm that many are going to be lost and few are going to heaven is not judgmental; it is the truth of God's word! This is an important point to stress.
From there I would focus upon Matthew 7:21-23 and some related questions. Jesus said - "Not everyone who says to Me, 'Lord, Lord,' shall enter the kingdom of heaven, but he who does the will of My Father in heaven. Many will say to Me in that day, 'Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?' And then I will declare to them, 'I never knew you; depart from Me, you who practice lawlessness!'" (cf. Luke 6:46).
Matthew 7:21-23 is very powerful and explicit. The one I am speaking with may start to struggle here. He may want to avoid this passage or focus on something else, but I will (if necessary) keep bringing him back to it kindly yet firmly with questions. Christ's words are clear, and I want the person I am speaking with to acknowledge the reality that only those who do the will of the Father can go to heaven. Therefore, it is implicitly true that those who do not do the will of the Father will go to hell. To affirm this is not judgmental; it is God's truth (whether we like it or not). One cannot accept part of what God's word teaches and reject other portions he finds less appealing. That will never work.
And now we're ready to deal with the original question (or accusation) more specifically: "Do you think that only members of the church of Christ will go to heaven?" I would ask at this point: "What does the phrase 'church of Christ' mean to you?" If he indicates that he views it as a name and therefore a denomination (as if it is just one small part of the universal church), then I would ask: "Does Scripture give a formal name to the church that Jesus built?" I believe the answer is "no". God doesn't name it, but He does describe it in Scripture. If someone pointed to my residence and said, "That's the house of Stephen," we would understand it as a description, not a name. The phrase "house of Stephen" means that the house belongs to Stephen; it is Stephen's house. Likewise, the phrase "church of Christ" is a description, not a name (though some are careless with this distinction and consequently cause much confusion). "Church of Christ" means that the church belongs to Christ; it is Christ's church! That's all I mean when I use the phrase. It might be necessary at this point to spend some time addressing the concept that there is only one church (i.e., the one that Jesus built; cf. Matt. 16:18). There is only "one body" (Eph. 4:4) and that "the church" is "His body" (Eph. 1:22,23).
From there I would ask: "Will Jesus save anyone who is not in His church?" If the reply given is "yes," I would ask for Biblical evidence for that view. Scripture should be explored to show that Jesus will save His church--the body (cf. Eph. 5:23). He will save those who obey Him (cf. Heb. 5:9). Furthermore, "How does one get in Jesus' church?" Taking time to go through the gospel plan of salvation is important here. There are a host of verses that clearly show the need for one to develop faith, repent of sin, confess Christ, and be immersed in water for forgiveness (cf. John 8:24; Luke 13:3; Rom. 10:9,10; Acts 2:38; 22:16; etc.). Those who are saved are automatically added to Jesus' church by God (cf. Acts 2:47). That's what the church is today--those who have been saved by grace through faith! One cannot be saved from sin today without being in Jesus' church (if so, where is the Biblical evidence?). II Timothy 2:10 reveals that salvation is "in Christ Jesus", and Galatians 3:27 teaches that one must be "baptized into Christ." Bible baptism is the culminating act that puts one into Jesus' church, which is where the saved are today. Then, it is up to that individual to remain faithful and to continue doing the Father's will that he might one day go to heaven (cf. Matt. 10:22; Rev. 2:10). Such a one will believe, practice, and teach the pure, unadulterated gospel of Christ--nothing more and nothing less (cf. Gal. 1:6-9). Tragically, there are many (according to Jesus Himself in Matt. 7:21-23) who claim allegiance to Christ but their claim is empty and hopeless since they do not do the Father's will.
If I combine all of the above principles, I can now rephrase the question and ask: "Do you think that today only those who faithfully do God's will and are in Jesus' church will go to heaven?" Now that our terms have been clarified and we have consulted Scripture, I will gladly answer "yes" to that question. To answer in that fashion is not judgmental; it is what God's word teaches.
Friends, when it comes to salvation, I'm not the judge and neither are you. If God says someone is saved, then I can say that. If God says someone is lost, I can say that, too (though it gives me no pleasure to do so). God is always right! Let us close with II Thessalonians 1:8,9 which powerfully reiterates some of the principles we've considered - "In flaming fire taking vengeance on those who do not know God, and on those who do not obey the gospel of our Lord Jesus Christ. These shall be punished with everlasting destruction from the presence of the Lord and from the glory of His power." Friends, do you know God and have you obeyed the gospel of Christ? You must if you want to be among the few on the narrow path to life! You must be a faithful member of the church that belongs to Jesus if you want to go to heaven. If we can be of service to you in any way, please do not hesitate to contact us.