2 John 1:10

If any one cometh to you, and bringeth not this teaching, receive him not into your house, and do not bid him good speed.

Titus 3:10

A man that stirs up divisions, after a first and second admonition, avoid;

Galatians 1:8-9

But even if we or an angel from heaven should preach a gospel to you contrary to that which we preached to you, let him be accursed!

Romans 16:17-18

But I exhort your brethren, to mark those who are causing divisions and offences, contrary to the doctrine which ye learned; and avoid them.

But this is what I wrote you, not to keep company with any one called a brother, if he be a fornicator, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner; with such a one not even to eat.

2 Thessalonians 3:6

Now we charge you, brethren, in the name of the Lord Jesus Christ, that ye withdraw yourselves from every brother that walketh disorderly, and not after the tradition which they received of us.