As far as I can tell, after thirty years of experiencing God and life as a "Christian" and after thinking about this experience from several perspectives, a Christian is...
a person who has a personal heart-to-heart relationship with the living God, characterized by warm and active acceptance on God's part; our honesty and dependence on the activities of Jesus Christ.
Let's look at this a little more closely.
"A personal heart-to-heart relationship":
The point of this is to exclude 'religious' relationships, in which an 'object' is revered 'from afar' but not approached in a personal way. God is indeed an 'awesome entity' but he is nonetheless a Person. A personal relationship is a ...view middle of the document...
.. all the aspects of personal existence. He is not a force or an attitude or a "perspective on the universe". We walk around our lives 'face to face' with this One-- even if we ignore Him.
"Characterized by warm and active acceptance on God's part":
From God's side, He accepts us. But this is not merely a 'political' acceptance--it has a warmth and joy to it. He 'smiles' upon us. He delights in us(!). This is more than simply the very important 'peace with God'; it is an active relationship. He gets involved in our lives for good--for our growth, our development, our character, our fulfillment, our stability, our significance in the lives and futures of others. He is always 'glad to see us'.
"Characterized by our honesty and dependence on":
From our side, the relationship is one of honesty about who He is and who we are. We are not 'gods', and as such need our Maker for the realization of the purposes for which we appear in this universe. We are a people dependent on the universe He has produced, and we are people whose goodness has been severely compromised by our regular moral failures and pervasive spiritual apathy.
The main thing in the universe that God the Father loves...is God the Son. When we are honest with the Father about who his Son is, and what he did in history for us, God welcomes us into this warm relationship...We simply have to be honest with Him...