In my personal reading today, two chapters appeared together, 1 Corinthians 15 and 1 John 4, both making the connection between doctrine and association with false teachers. Paul cites a poet, in proverbial form, to warn against the danger of fellowship with those who teach false doctrine.
Do not be deceived: “Bad company corrupts good morals.” Sober up as you should, and stop sinning! For some have no knowledge of God—I say this to your shame!
1 Corinthians 15.33-34 NET
The bad company are those who taught that there was no resurrection. By extension, today, they are those who teach any false doctrine. They must be avoided. False teachers in our midst must be removed.
The lack of knowledge, Paul says, is sin. For ignorance does not exist in a vacuum. False teaching occupies the space of truth, takes its place. It’s our responsibility to know the truth, through reading and study of the Scriptures, which were given to us for this purpose, among others.
The phrase “as you should” comes from the word for righteous or just. They must act correctly, rejecting both the false doctrine as well as those who promote it. Pride leads to wrong action. God requires that we take right action, living as disciples who will not accept indolence or looseness in morality, doctrine, or service.
Such a situation was shameful for the Corinthians. They had many spiritual gifts, but badly employed; they had great pride in themselves, but they should have felt ashamed for the situation in which they found themselves.
Some congregations today find themselves in similar state, greatly blessed by the Lord, but exalting themselves in their liberties and supposed maturity. Actually, their tolerance for departures from the gospel is a motive of shame before the saints and before the Lord.