Susan, unless you can define Christianity in a way that is accepted by all who claim it then there is no possible way to do what you are asking in love. If we are to judge Christians we are required to do it in love. But how do we define it.
How many different beliefs on Doctrinal issues are there in this forum alone.
Some say Catholics believe salvation lies within the Church and therefore they are not Christians. While some Catholics say anyone outside the Catholic Church are not Christians.
Some others say you must be baptized to be saved and others say no, and many on each side saying those with opposing views are not Christian.
So how do we decide who fits whose definition of Christian? If you are talking about exposing a sin in some person's life and bringing them to judgement and accountability in a public forum, under NO CIRCUMSTANCES are you to do that ever.
No where in God's Word is anyone ever given that right. If you do, you better be sure there is no sin in your life, because the Word teaches that you will receive the greater condemnation for it.
Jesus stated it VERY CLEARLY in John, chapter 8, verse 7: "So when they continued asking him, he lifted up himself, and said unto them, He that is without sin among you, let him first cast a stone at her."
I don't believe there are any of us without sin so none of us should cast stones at anyone.
If on the other hand you are talking about pointing out the fact that cultsare teaching false doctrines and their leaders are false prophets, then that is a different story altogether.
But even there you need to know what you are talking about. You need to hold up what they are teaching to the light of the Word and see that it does not line up, and be sure that the Word is your guide before you do it.
But I don't believe that Jesus sent us on a mission to seek and destroy Christians. He specifically says He saved us to BEAR Fruit, and to reproduce ourselves. With time running out as it is and with all the lost who desperately need Jesus, I believe we can better serve Jesus, by keeping our eyes firmly fixed on Him and doing all in our strength to obey all His commands. We need to seek His forgiveness and to grow and be busy telling the Good News of Jesus every where we go and in everyway we can.
I believe we should be busy building up and edifying rather than concentrating on the destruction of Christians who have sinned.