Why is fellowship not allowed with churches bearing a different name than, "_ church of Christ"? Christ's church is not limited to a specific geographical location is it? Is not the phrase "churches of Christ" referring to the individual 'ekklesia' of the Church Universal, rather than a mandated title? For example, in my own home there is an ekklesia, or those 'called out' as one may note in Romans 16:5. If the church names itself as, "Greenleaf Christian Fellowship", why does that damn that group if what is taught from it's pulpit is indeed scriptural? Note this question may not apply to your particular stance, but the group I find myself contending with do see the name on the door as an issue of disobedience and therefore of a salvific nature.
Fellowship does not depend on what a group is called, but rather depends on whether that group is part of the body of Christ. Those in the body of Christ are in fellowship with each other, but not with those outside the body of Christ. We become part of the body of Christ when we are buried with him in baptism and put on Christ. (See this lesson for more about baptism and see this page for more about God's plan of salvation.) A faithful congregation of believers follows the pattern for proper organization and worship laid out in the Scriptures.
"Church of Christ" is not the name of the Lord's church but rather is its description. It is the church that was purchased by and that belongs to Christ. The sign could just as easily read "The Lord's Church," or "God's Church," or "The Body of Christ," or "The Church," etc. It would not be correct, however, to put on that sign some man-made designation not found in the Bible because such would suggest that the church is a man-made organization rather than an eternal kingdom not made with human hands.
Sadly, many who today sit idly by while heresy is proclaimed from their pulpits would rise up in arms if someone tried to change the "name" on the sign outside. There are many groups calling themselves "Church of Christ" that likely lost their candlestick years ago. Conversely, there may very well be groups calling themselves something else (such as, for example, a Christian Fellowship) that are faithful congregations of the Lord's body. The test is whether they follow the word of God rather than whether they put the right magic words outside on their sign.
You Must Hear the Gospel
Romans 10:17
You must hear the gospel and then understand and recognize that you are lost without Jesus Christ no matter who you are and no matter what your background is. The Bible tells us that “all have sinned, and come short of the glory of God.” (Romans 3:23) Before you can be saved, you must understand that you are lost and that the only way to be saved is by obedience to the gospel of Jesus Christ. (2 Thessalonians 1:8) Jesus said, “I am the way, the truth, and the life: no man cometh unto the Father, but by me.” (John 14:6) “Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved.” (Acts 4:12) "So then faith cometh by hearing, and hearing by the word of God." (Romans 10:17)
You Must Believe
Hebrews 11:6
You must believe and have faith in God because “without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.” (Hebrews 11:6) But neither belief alone nor faith alone is sufficient to save. (James 2:19; James 2:24; Matthew 7:21)
You Must Repent
Acts 3:19
You must repent of your sins. (Acts 3:19) But repentance alone is not enough. The so-called “Sinner’s Prayer” that you hear so much about today from denominational preachers does not appear anywhere in the Bible. Indeed, nowhere in the Bible was anyone ever told to pray the “Sinner’s Prayer” to be saved. By contrast, there are numerous examples showing that prayer alone does not save. Saul, for example, prayed following his meeting with Jesus on the road to Damascus (Acts 9:11), but Saul was still in his sins when Ananias met him three days later (Acts 22:16). Cornelius prayed to God always, and yet there was something else he needed to do to be saved (Acts 10:2, 6, 33, 48). If prayer alone did not save Saul or Cornelius, prayer alone will not save you. You must obey the gospel. (2 Thess. 1:8)
You Must Confess
Romans 10:9
You must confess that Jesus Christ is the Son of God. (Romans 10:9-10) Note that you do NOT need to make Jesus “Lord of your life.” Why? Because Jesus is already Lord of your life whether or not you have obeyed his gospel. Indeed, we obey him, not to make him Lord, but because he already is Lord. (Acts 2:36) Also, no one in the Bible was ever told to just “accept Jesus as your personal savior.” We must confess that Jesus is the Son of God, but, as with faith and repentance, confession alone does not save. (Matthew 7:21)
You Must Be Baptized
Acts 2:38
Having believed, repented, and confessed that Jesus is the Son of God, you must be baptized for the remission of your sins. (Acts 2:38) It is at this point (and not before) that your sins are forgiven. (Acts 22:16) It is impossible to proclaim the gospel of Jesus Christ without teaching the absolute necessity of baptism for salvation. (Acts 8:35-36; Romans 6:3-4; 1 Peter 3:21) Anyone who responds to the question in Acts 2:37 with an answer that contradicts Acts 2:38 is NOT proclaiming the gospel of Jesus Christ!
You Must Be Faithful Unto Death
Revelation 2:10
Once you are saved, God adds you to his church and writes your name in the Book of Life. (Acts 2:47; Philippians 4:3) To continue in God’s grace, you must continue to serve God faithfully until death. Unless they remain faithful, those who are in God’s grace will fall from grace, and those whose names are in the Book of Life will have their names blotted out of that book. (Revelation 2:10; Revelation 3:5; Galatians 5:4)