The Christian church is supposed to be a community of kindness, and one of the results of that kindness is that people who are not accepted in other places because of their behaviour are welcomed in churches. However, this means that churches face problems in dealing with people who exhibit anti-social behaviour. In his letter, Jude refers to difficult people and the troubles they can cause for the church:
Dear friends, I really wanted to write to you about the salvation which we share, but I find it necessary to write to encourage you to fight for the faith which was given once for all to the believers. Some people have secretly infiltrated you. Their condemnation was written about long ago, and they are ungodly, turning the grace of our God into a pretext for immorality, and denying our only Master and Lord, Jesus Christ.
There is a difference between showing an accepting attitude to people who have been rejected by others and tolerating conduct which is damaging to the integrity of the church. When someone is derailing the mission of the church and leading others astray, firm action is required. Without ever giving up on loving the unloved, the church needs to fight for the faith.