I feel like you’re saying a believer should never call a sin that someone may be doing, a sin. There is specific scripture regarding confronting a significant sin or sins that a member of the body may be involved with. And as far as sins by those who are not believers, if Christians don’t speak out, the unsaved will think “everything is OK; there is no real right or wrong”. Just sitting in our churches and waiting for the “convicted” to walk in is too easy. I still believe we have a responsibility to “call sins what they are, sins”, and of course with a heart and mind of humility and/or forgiveness if its we who were the victim.
I understand what you’re saying, but please read all of Matt. 18 before you write me off as a lunatic. It deals with being sinned against by a brother, and the requirement that we forgive each other.
As for non-believers, much more harm than good has been done by well meaning Christians running off ahead of the Holy Spirit, trying to “help” Him convict someone of their sin. Romans 8:29-30 says that the Lord foreknew us, He predestined us, He calls us, and He will glorify us. Matthew 16:18 says He will build the Church. In His good time everyone he foreknew will be called and will come. He doesn’t miss anyone.
Our job is to listen for His prompting, because that means He’s choosing us to help Him call someone He has convicted. But we call people by sharing the Good News that the sins they feel conviction about will be forgiven if they ask. It’s God’s kindness that leads people to repentance, (Romans 2:4) not His judgment.