Share 'Evangelism and the Law'

What role does the 'Law' play in evangelism? I've brought this up before in church discussions; that we should both live the law as examples and share the law with those we evangelize. The typical response is, "No, no, just love people." While some people do indeed use the law to beat people over the head doesn't the law come from love? Are the law and love totally divorced from eachother? Does...