What I think is being talked about here is people judging each other in their personal exchanges. Jesus said Love your enemies, do good, and loan not expecting to be paid back. In doing this God will reward you, and it will be great, and you will be called the children of lthe Highest. God is kind to the unthankful and the evil people. Be merciful because your Father in heaven is merciful. We are not to judge each other, but let God judge. We are not to give condemnation to other if we don't want to be condemned ourselves. If we want to be forgiven we need to forgive others. If we give God will cause others to give to us also. According to Jesus' teaching the same way we give, in that way it will be returned to us. The blind leading the blind is what the Pharisees were doing. They didn't know where they were going, and they were trying to show others which way to go. Verses 41; and 42; are talking about a person trying to correct someone else when that person has the same problems or maybe even worse problems. The person is trying to find fault, correct a fault when that person has worse faults. This has to do with being spiritually blind. Before a person can correct someone else's fault that person needs not to have faults. Jesus is talking about someone finding small faults in others when that person has huge faults.
It is not bad to provide correction for someone with the intention of helping them. This is like constructive criticism with the intention of being helpful, or being critical with the purpose of hurting and being descructive to the other person.
Thank you, Red, for the invitation to preach in your church! That would be a pleasure!
