“For just as we have many members in one body and all the members do not have the same function, so we, who are many, are one body in Christ, and individually members one of another.” ~Romans 12:4-5
What is the body of Christ? It is the church UNIVERSAL. It is the collective grouping of ALL BELIEVERS worldwide. While it is true that in the local body, we are all vital parts, each one of us is very much a part of the universal body of Christ of which He is the head, and no other.
While we have shepherds whom He has charged with caring for the different local parts of His body, it is evidenced in Scripture that believers absolutely did move from one local body to another as they were needed. They did not move because they were upset or angry about one place (at least, that is not recorded), but because they were truly moved by the Spirit of God to invest in a certain body for a season of their lives as needed.
It is also noted in Scripture that there are times when differences are irreconcilable, and a separation is needed, as evidenced in the case of Paul, Barnabas, and John Mark. (Acts 15:36-41) We see that in this story, Paul did not trust the actions of Mark, who had failed them at one point, but Barnabas saw something redeemable in him. They parted, Paul to do as the Spirit led him, which was to minister to the body, and Barnabas to do as the Spirit led him – which was likely to minister to and disciple Mark. This seems to be probable because we later see that Paul actually asks for Mark, calling him valuable to the ministry. (II Timothy 4:11)
What if they had insisted on staying together? Would Mark have ever completely recovered from his previous fall? Or would Paul, because of his very direct nature, have kept him in a somewhat subservient role of never being quite “good enough” because of his previous faults? Distance and time were needed for Mark to recover and for Paul to get over his frustration. The Spirit led them on two different paths, which eventually came back together, because they were part of ONE BODY.
I think this story teaches an important lesson. If we truly believe that each one in the body is indwelt by the Holy Spirit of God, then we must also believe that it is possible for each member to be led by the Spirit, even after they have failed. This is not to say that that is always the case, as we see clearly that it is possible to live according to the flesh, even after receiving the Spirit, and thereby grieve Him. That being said, it is not our place as believers to tell another that they are or are not being led by the Spirit, outside of obvious sinful behavior. (Romans 14:12)
Understanding this, what then should be our reaction when a brother or sister leaves the local body to become part of another? It is my humble opinion that we should trust that as a believer, they have sought God, and that He has led them to make that decision. We should be very careful about casting judgement on our fellow believers and understand that the Spirit uses many different scenarios and situations to get His people where He wants them, including disagreements, as clearly evidenced in the aforementioned story.
There is nothing in Scripture to indicate that believers must be tied to only one local church fellowship for life, but rather,
“There is one body and one Spirit, just as also you were called in one hope of your calling; one Lord, one faith, one baptism, one God and Father of all who is over all and through all and in all.” ~ Ephesians 4:4-6
So if you are a part of a local body, and that is where you stay for life, and your children are born there, and your grandchildren, and so forth, then that is wonderful, and beautiful, and a testimony to the love and fellowship that is there in Christ.
But when another believer does not make that same choice, instead of being offended we should rather be encouraged that they are choosing to remain a part of a local body, in fellowship with other believers, and being encouraged by the Word. Any offenses should be forgiven, and ALL attempts should be made to remain at peace, not only within the one local body but with other local bodies as well.
None of us are allowed to have an “us and them” mentality, but are required by God to be “DILIGENT to preserve the unity of the Spirit in the bond of peace,” (Ephesians 4:3) and recognizing that even as various local bodies, we each have a place and function in the universal body of Christ that is different from the others. Rather than being at odds with one another over church members and methods, we should move as one body in spreading the message of Christ, however Christ the head sees fit to move us.
“And He put all things in subjection under His feet, and gave HIM (Christ) as head over all things to the church, which is HIS body, the fullness of Him who fills all in all.” ~ Ephesians 1:22