Not, you should judge. Not, you should ridicule them. Not, you should stroke their ego and say God's grace covers everything. None of that. But PRAY. Pray to God. Not picking up the phone, or sending a text, or message to tell someone and discuss, but to pray. Why?
Because God is the ONLY ONE Who will know what the unique situation calls for. He may need us to respond with correction when we might have responded with grace. He may need us to be loving and understanding when we may have wanted to practice tough love. He knows what is needed to bring glory to HIS name in our lives and it may not be what we thought it would be. Just look at the examples of the religious of the time.
Humbling ourselves in order for the Lord to be exalted and have our brothers and sisters given life is what is important, not our opinions on the matter.