Why Repentance doesn't click with some people. Sharing our faith with unbelievers.

I have been arguing with an outright aetheist in Duluth, MN for several months who completely refutes the idea of any organized religion or origin of People of the Book.  He does not look into or review the historical pretexts of early Christianity, stemming from Judaism, to modern day.  I am finding tools to witness to him.  We will have our regular hosts on and also i invited a few Christian believers to share their faith and what God has done for them.  Nancy from the Twin Cities called in about her online ministry.  We had a Bohemian style Christian call in from Northern California who shared his conceptions of the Old Testament and could correlate chapter and verses to the originis of the Jewish and Christian faith.