Last night at Trinity Church in Boston Rob Bell responded to a question about how an Episcopal parish could become a mega-church. Rob's first point was that size isn't the issue and that small churches are not less important than big ones. His second point was that what draws people to a church is often friendship with one of its members. He told us that he had once asked another pastor who wanted his church to grow if he had friends who weren't members of the church. The pastor didn't. Bell said that he - and others at Mars Hill Bible Church - try to make lots of friends in the community and that those friendships are often what draw people to Mars Hill. In the Happening and Cursillo movements this idea is often expressed as "Make a friend. Be a friend. Bring a friend to Christ."
I think friendship is important, although I sometimes worry that we might see our friendships with those outside the church as purely instrumental, as only for the purpose of increasing church membership. Friends are important, simply as friends, and not as prospects for membership.