Disclaimer:  The proper way to address this question is to read the whole New Testament with this question in mind, writing down all passages that pertain.  Unfortunately, I didn’t have the time, so I merely assembled the passages that came to mind.

Separating from certain people had a reason:

  • 2 Thessalonians 3:14 Concerning the lazy (disorderly: v6, 11), “do not keep company with him that he may be ashamed.”
  • 1 Corinthians 5:5 Concerning the one who had his father’s wife, “deliver such a one to Satan for the destruction of his flesh, that his spirit may be saved in the day of the Lord” because such behavior spreads (v6 – 7), is inconsistent with sincerity and truth (v8), and even the Gentiles abhor it (v1).
  • 1 Timothy 1:19 – 20 Some, having rejected concerning the faith, have suffered shipwreck,  of whom are Hymenaeus and Alexander, whom I delivered to Satan that they may learn not to blaspheme.
  • 2 Timothy 3:1 – 9 …having a form of godliness but denying its power.  From such people turn away.
  • 2 Timothy 2:14 – 18 Remind them of these things, charging them before the Lord not to strive about words to no profit, to the ruin of the hearers…but shun profane and idle babblings for they will increase to more ungodliness, and their message will spread like cancer.

Harsh words for those who perverted the gospel:

  • Romans 3:8 Their condemnation is just.
  • Galatians 1:9 Let him be accursed.
  • Galatians 5:12 Concerning those who try to bring law into the church (3:1 – 11), “I could wish that those who trouble you would even cut themselves off.”
  • Jude 4 “For certain men have crept in unnoticed, who long ago were marked out for this condemnation…”
  • 1 Timothy 4:1 – 3 Some will depart from the faith, giving heed to deceiving spirits and doctrines of demons, speaking lies in hypocrisy, having their own conscience seared with a hot iron.
  • Matthew 23:13 – 39 Woe to you, scribes and Pharisees, hypocrites.  For you shut up the kingdom of heaven against men; for you neither go in yourselves nor do you allow those who are entering to go in.
  • Philippians 3:2 Beware of the dogs; beware of the evil workers; beware of the mutilation.

Causing division was abhorred:

  • Titus 3:10 – 11 Reject a divisive man after the first and second admonition, knowing that such a person is warped and sinning, being self-condemned.
  • Jude 19 These are worldly people, who cause divisions, not having the Spirit.

While promoting growth among the faithful, those who admonish demonstrated tolerance

  • Jude 9 Yet Michael the archangel, in contending with the devil, when he disputed about the body of Moses, dared no bring against him a reviling accusation, but said, “The Lord rebuke you.”
  • Paul wrote 1 Corinthians and Galatians to correct a large number of problems, yet recommended separation for only one. Paul described those in all the other bad situations as “brethren.”
  • James described several failures in the church, but called them brethren.
  • Galatians 6:1 Brethren, if a man is overtaken in any trespass, you who are spiritual restore such a one in a spirit of gentleness, considering yourself lest you also be tempted.”
  • 1 Thessalonians 5:14 Now we exhort you, brethren, warn those who are unruly, comfort the fainthearted, uphold the weak, be patient with all.
  • 1 Timothy 1:3 – 11 Charge some that they teach no other doctrine
  • 1 Timothy 5:1 – 2 Do not rebuke…but exhort as family
  • Titus 1:13 Rebuke them sharply that they may be sound in faith.
  • Philippians 3:12 – 14 Bearing with one another, forgiving one another…even as Christ forgave you.

Past failures prepare us to be compassionate

  • Luke 22:31 – 32 “Simon, Simon, indeed Satan has asked for you, that he may sift you as wheat.  But I have prayed for you, that your faith should not fail; and when you have returned, strengthen your brethren.”
  • 1 Timothy 1:13 – 14 I obtained mercy because I did it ignorantly in unbelief…Christ Jesus came into the world to save sinners, of whom I am chief.
  • 2 Corinthians 4:7 We have this treasure in earthen vessels that the excellence of the power may be of God and not of us.
  • Ephesians 2:5 …even when we were dead in trespasses, made us alive together with Christ…
  • 1 Corinthians 6:11 And such were some of you, but you were washed, but you were sanctified, but your were justified in the name of the Lord Jesus and by the Spirit of our God.

Our attitude toward the lost

  • Luke 19:41 – 44 Jesus wept over the plight of Jerusalem
  • Romans 9:3 For I could wish that I myself were accursed from Christ for my brethren, my countrymen according to the flesh
  • Philippians 3:18 – 19 For many walk, of whom I have told you often, and now tell you even weeping, that they are enemies of the cross of Christ; whose end is destruction
  • Colossians 4:6 Let your speech always be with grace, seasoned with salt, that you may know how you ought to answer each one.