Read Matthew 18
Jesus answered Cain’s question: Am I my brother’s keeper?
And the answer is, yes. We serve God, honor God, love God and each other but we are in this together. We look out for one another. We share burdens. We encourage each other.
We like that part. We like to skip over the part about confronting our brothers and sisters when they go astray, but did we just not read about the man who goes after the 1 and leaves the 99 in the open country? Do you suddenly decide to right off the 1 because it might be a difficult conversation?
Be private. Be gentle. Bring help if needed. Garner the support of the entire body if you must, but don’t write off the person who has strayed. Remember he or she is still of value to you Father in heaven, who loves them very much.
Christian up and do your part.
OBTW—when 2 or 3 gather in his name, Jesus is in your presence so it’s not you judging your brother. You are bringing the Truth to them. The church has been given power and authority in this age. Use it to fulfill the will of the Father.