"What is a true Christian?" - D. Martyn Lloyd-Jones

“The man who is truly Christian is the man who has come to realize that God is the most important Person in all his life. What is a Christian? I define him as the man who has come to realize he has a soul and that he has lost that soul in a spiritual sense. He is a man who realizes he is guilty before God. He is a man who has come to see that what matters is the destiny of his soul. He was interested in other things, but he knows they will all disappear when the soul still goes on. He sees judgment to come, and because of all this, he now sees the most important thing of all – ‘I need salvation, I need forgiveness, I need a new life, I need to be reconciled to God!’ Is there anyone who can help? Yes, there is, and he turns to Christ and says, ‘I will not let Thee go, I must have this blessing.’ For this he pleads, for this he cries – it is now the supreme interest in his life. May I again put my simple question. Is this the biggest thing in your life? If I ask tonight from this pulpit what is the one thing to which you would hold if everything else has to go, what would you say? Would you hold on to Christ at the expense and the cost of everything else? That is the mark of the Christian. He sees that it is Christ dying on the cross that alone can give him forgiveness of sin. He sees it is in Christ alone he is given a new life and a new nature and a new standing before God. He sees it is in Christ, who has conquered death and the grave, that he is given an eternal and glorious inheritance. He sees all that in Christ and he says, ‘Though I am bereft of everything, as long as I have him all is well.’ Is Christ supreme in our lives? Do we know that this is the most vital thing and would we gladly sacrifice everything else for the sake of this? That is what Jacob came to feel. It has always been the feeling of every true Christian.”

- D. Martyn Lloyd-Jones, Old Testament Evangelistic Sermons,
Before and After Penuel: The Evidence of True Conversion

http://www.monergismbooks.com/Old-Testament-Evangelistic-Sermons-p-18605.html