8 Bible Verses about Division Among Christians

And some men came down from Judea [and] began teaching the brothers, "Unless you are circumcised according to the custom [prescribed] by Moses, you cannot be saved." And [after] there was no little strife and debate by Paul and Barnabas against them, they appointed Paul and Barnabas and some others from among them to go up to the apostles and elders in Jerusalem concerning this issue. So they were sent on their way by the church, [and] passed through both Phoenicia and Samaria, telling in detail the conversion of the Gentiles and bringing great joy to all the brothers.read more.
And [when they] arrived in Jerusalem, they were received by the church and the apostles and the elders, and reported all that God had done with them. But some of those who had believed from the party of the Pharisees stood up, saying, "It is necessary to circumcise them and to command [them] to observe the law of Moses!"

Now I exhort you, brothers, to look out for those who cause dissensions and temptations contrary to the teaching which you learned, and stay away from them.

Now I exhort you, brothers, by the name of our Lord Jesus Christ, that you all say the same [thing] and there not be divisions among you, and that you be made complete in the same mind and with the same purpose. For it has been made clear to me concerning you, my brothers, by {Chloe's people}, that there are quarrels among you. But I say this, that each of you is saying, "I am with Paul," and "I [am] with Apollos," and "I [am] with Cephas," and "I [am] with Christ."read more.
Has Christ been divided? Paul was not crucified for you, was he? Or were you baptized in the name of Paul?

for you are still fleshly. For where [there is] jealousy and strife among you, are you not fleshly, and do you not live like [unregenerate] people?

Does anyone among you, [if he] has a matter against someone else, dare to go to court before the unrighteous, and not before the saints?

For in the first place, [when you] come together as a church, I hear there are divisions among you, and in part I believe it.

Beware of the dogs, beware of the evil workers, beware of the mutilation.

They went out from us, but they were not of us; for if they had been of us, they would have remained with us. But [they went out], in order that it might be shown that all of them are not of us.