See Matthew 18:15-17. Understanding that this is if someone sins against you it should still apply to a brother or sister whom you suspect are in sin. **Remember that sin is an offense against God and only God realizes when a sin has been committed. **We cannot judge the heart of another but we can observe when someone is going down the wrong path and counsel them. While perhaps being a sin of omission, I hardly find it a mortal sin if we fail to confront someone of their sinful behavior. It is more an act of charity and if we love our brothers and sisters in Christ we would want to see them follow the way of Christ in their outward behavior while at the same time being careful not to judge their souls…teachccd
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