2 John 1:10
If anyone comes to you [i.e., to your meetings] who does not bring this teaching [about Christ], you should not welcome him into your home or give him [any] greetings [i.e., suggesting approval or endorsement].
Titus 3:10
After you have warned a divisive person twice, have nothing more to do with him [i.e., withdraw spiritual fellowship from him].
Galatians 1:8-9
However, if we [apostles] or even an angel [claiming to be] from heaven were to preach any other "gospel" than the one we have [already] preached to you, let that person be cut off from God's [salvation].
Romans 16:17-18
Now I urge you, brothers, watch out for those who are causing divisions and occasions for falling [away from God over matters] contrary to the teaching you have learned, and withdraw from them [i.e., stop listening to their false teaching].
1 Corinthians 5:11
But I wrote to you not to associate with anyone claiming to be a [Christian] brother who is [guilty of being] sexually immoral, or greedy, or an idolater, or who speaks abusively, or a drunkard, or a swindler. Do not even eat [a social meal] with such a person.
2 Thessalonians 3:6
Now we command you, brothers, in the name [i.e., by the authority] of our Lord Jesus Christ, that you people stay away from every brother [or sister] who lives an idle life [See note on I Thess. 5:14], and not according to the [inspired] tradition which you received from us.
2 Thessalonians 3:14
And if any person does not obey our instructions, [given] in this letter, you should take note of him so that you do not associate with him, in hope that he will become ashamed [of his conduct].
1 Corinthians 16:22
If anyone [there] does not love the Lord, he deserves to be cut off from God. O Lord, come [back soon].
2 Timothy 3:5-6
[These people] maintain an appearance of being godly, but they have denied its power; [you should] turn away from such people.
2 John 1:11
For the person who greets him [with approval] participates in his evil deeds [i.e., in his false teaching].