There is this string of amazing quotes in the second chapter of Brennan Manning's book The Importance of Being Foolish. I have been chewing on them for days and they speak of this very same issue. He says it better than I ever could, so I am just going to type them all in and leave it at that.
"The Communist who accepts Karl Marx but not his doctrine is scarcely different from the Christian who accepts Jesus Christ but refuses to shape his life according to Christ's teaching." pg 43
"Authentic, evangelical faith cannot be separated from a readiness to act on the Word of God according to present opportunities."
"Soren Kierkegaard describes two type of Christians: those who imitate Jesus Christ and a second much cheaper brand-those who are content to admire him." Pg 45
A 23 year old woman dong grad work at the University of Paris writes:
"To me a Christian is either a man who lives in Christ or a phony. You Christians do not appreciate that it is on this- the almost external testminoy that you give of God- that we judge you. You ought to radiate Christ. Your faith ought to flow out to us like a river of life. You ought to infect us with a love for him. It is then that God who was impossible becomes possible for the atheist and for those of us whose faith is wavering. We cannot help being struck, upset, and confused by a Christian who is truly Christlike. And we do not forgive him when he fails to be."
"The great mark of a Christian is what no other characteristic can replace, namely the example of a life which can only be explained in terms of God." Pg 48
"Contact with Christians should be an experience that proves to people that the gospel is a power that transforms the whole of life." Pg 49