"We tend as Christians not to know what to do with non-Christians other than to say; "You're wrong". There are an awful lot of sermons that go like that. Here's how the sermon goes; "We believe this and this. You out there in the world around us don't believe this and this. We are right. You are nowhere near right. Let us pray. And we pray that the Holy Spirit will convict you through my words as negative and as blunt as they are".
There's another way to go here! Every culture has got some things that they appreciate about Christianity and some things they hate about Christianity. The attractive parts are A-Doctrines and the unattractive doctrines are B-Doctrines. Both are true. If you want to preach B-Doctrines in a way that is disarming and engaging then you have got to float the B-Doctrines on a raft of A-Doctrines. If you put the stones together in a river they will sink".
Tim Keller - "Preaching the Gospel" - Newfrontiers Leaders Conference at Westminster Chapel - Wednesday 25th February 2009.