If we are "to note that man" who does not obey the truth, "and have no company with him, that he may be ashamed" (2 Thessalonians 3:14; 1 Corinthians 5:11) does this mean are we not to be friends with unbelievers? No, Paul is referring to people who say they are believers but who do not live according to God's word.
Paul wrote to the Corinthians that to avoid having company with fornicators, or with the covetous, or extortioners, or with idolaters we would have to go out of the world. (1 Corinthians 5:10). We know Jesus ate with sinners (Matthew 9:10-13).
Nor does it mean we turn our backs on a fellow believer that has momentarily fallen to a temptation and has a repentant heart. The strong rebuke belongs to the hypocrite who feigns obedience but refuses to give up his or her a life of sin.
