These passages were meant to prevent the very thing we do. We pronounce judgment upon our brethren because they disagree with us. Many times negative judgment stems from a disagreement about something of which the Bible is silent. We classed them as unbelievers because that s who the verses are warning about. We called them by Mister.
Legalism rationalizes such a crass attitude.
The Pharisees were dedicated legalists. They thought they could earn their way to heaven by complying with meticulous rules and regulations based upon their interpretation of a law, the Law of Moses. We have understood the Law of Christ to be a similar law and to think we can earn our way to heaven by strict adherence to our interpretations. Jesus said that the Pharisees made religion a burden. We have done the same when our religion should be a joy and help in our lives.