What binds all Christians together is their common faith in Christ. When I served at our faith-based recovery program it was that bond that most amazed me. We had people with all kinds of different life stories, all kinds of different experiences and abilities, all different races. What brought us all together despite these obvious differences was our common bond in Christ.
Philippians 4:21-23
(21) Salute every saint in Christ Jesus. The brethren which are with me greet
you.
(22) All the saints salute you, chiefly they that are of Caesar’s household.
(23) The grace of our Lord Jesus Christ be with you all. Amen.
Paul urges the Philippians to “salute every saint in Christ Jesus” (Philippians 4:21) Unlike many of his other epistles, he did not specifically name anyone and when he sends greetings to the Philippians, he says “all the saints salute you” (Philippians 4:22). The saints at Rome probably did not know any of the saints at Philippi (other than Epaphroditus) and the Philippians most likely did not know any of the saints in Rome, but they all knew the same Savior, Jesus Christ, and that is what brought them together.
We live in a very fragmented world. People are at odds often over things that are purely temporal and superficial. What mankind needs is a common bond in something that lasts through eternity and that crosses boundaries. That kind of bond is found in Christ.