A favourite argument is the phrase taken, I believe, from the Anglican Book of Alternative Services (although I could be wrong in this), "Jesus welcomes sinners and invites them to his table." This, I believe, is based on Luke 15:2,
But the Pharisees and the teachers of the law muttered, "This man welcomes sinners and eats with them."
This is then extended to mean that Jesus approved of sinners and did not judge them. But these people only consider half the case. This verse in in the context of the repentance of sinners. In verse 7 of the very same chapter Jesus says,
I tell you that in the same way there will be more rejoicing in heaven over one sinner who repents than over ninety-nine righteous persons who do not need to repent.In Luke 5:32 Jesus tells his whole purpose in associating with those thought of by society as sinners,
"...I have not come to call the righteous, but sinners to repentance."
These people will quote Jesus as saying to the woman taken in adultery (John chapter 8),
"Neither do I condemn you..."but neglect the rest of his sentence,
"...go and sin no more."
Would Jesus have done this woman a service; would he have shown himself kind and loving if he had said, "That's OK. Just go on living as you want. It doesn't matter"?
No. That would have been the ultimate disservice.