In dealing with those who aren't great fans of our church or our 16:5 conference – I typically talk to them about the Great Commission in explaining why we do what we do. I've been surprised by how many pastors can sleep at night when not making disciples through their church. I've often said, "You ought to lose sleep over the Great Commision."
But when I ran across this quote by Spurgeon – I realized maybe I'm not saying it strongly enough.
"The fact is, brethren, we must have conversion work here. We cannot go on as some churches do without converts. We cannot, we will not, we must not, we dare not. Souls must be converted here, and if there be not many born to Christ, may the Lord grant to me that I may sleep in the tomb and be heard no more. Better indeed for us to die than to live, if souls be not saved." – Charles Spurgeon