2 Timothy 4:2
Preach the word, Be ready in season and out of season. Convince, rebuke, exhort, with all longsuffering
and teaching. (2 Timothy 4:2)
Matthew 18:15-17 Dealing with a Sinning Brother
“Moreover if your brother sins against you, go and tell him his fault between you and him alone. If he hears you, you have gained your brother. But if he will not hear, take with you one or two more, that ‘by the mouth of two or three witnesses every word may be established.’ And if he refuses to hear them, tell it to the church. But if he refuses even to hear the church, let him be to you like a heathen and a tax collector.
and that repentance and remission of sins should be preached in His name to all nations, beginning at Jerusalem.
1 Corinthians 5:11
But now I have written to you not to keep company with anyone named a brother, who is sexually immoral, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner—not even to eat with such a person.
Pursue peace with all people, and holiness, without which no one will see the Lord
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.