How to Recognize a Christian:
I'm going to work with an informal definition of a Christian: a Christian is one who believes that the Jesus Christ described in the New Testament of the Holy Bible was/is divine and who wants to be on Jesus' good side. This brief guide will show you how to recognize one.
A quick preface:
The Christian probably believes that the laws of the Old Testament as handed down by God, Himself, no longer need to be upheld because of Christ's sacrifice. Relevant verses:
Romans 7:4,6: Ye also are become dead to the law by the body of Christ... We are delivered from the law, that being dead.
2 Corinthians 3:14: But their minds were blinded: for until this day remaineth the same veil untaken away in the reading of the old testament; which veil is done away in Christ.