I am not a Christian, by the way I dress, that I read the Bible every day, that I go to Church every Sunday or abstain from drinking and smoking. I am not a Christian because I have different colored hair or skin.
I am a Christian because of the LUXURY of Christ's death for me, because is in my heart, that I believe this. That, God so loved the world, he gave his one and only son, that whoever believes in him shall not perish but have eternal life. That, God not only exists, but also that he is GOOD.
This is what makes me a christian, the presence of God in my heart, changing me, refining me, from the inside out.