Is he a Christian? Are you?

Much has been made of late about whether or not someone who claims to be a Christian can be taken at his/her word as such.  Pope Francis even weighed in on this important issue, declaring that an attitude of wall building instead of the extending of love cannot reside in the mind of a Christian.  The Bible says much on this topic, from Jesus declaring that "all men will know that you are my disciples, if you love one another." (John 13:35) and also, "If a man remains in me and I in him, he will bear much fruit." (John 15:5)  The question of who really belongs to the Church became important even in that first generation of believers, as evidenced by the primary focus on that question of the apostle John's first letter.  I John contains a threefold test of true Christian faith: (1) Belief in Jesus Christ as the Son of God, (2) obedience to the commands of God, (3) and lastly, display of Christian brotherly love.  In essence, John is simply repeating the instructions of Jesus himself and adding to it the need to believe in Jesus (which Jesus was assuming by addressing his comments to his disciples, men who had already chosen to follow him).
Where does this leave us, then, when faced with someone who claims to be a Christian yet shows little or no evidence of spiritual growth in terms of obeying the commands of God by avoiding sin and seeking righteousness, nor much evidence of love, first for fellow brothers and sisters in Christ, and then for the Lost whom the Gospel obligates us to pursue with God's love?  If the evidence is lacking, and it ought to be clear enough to leave no doubt because we're talking about the overall direction of a life, not simply one or two moments, then the evidence is indeed lacking.  Without evidence of Christian faith, without fruit of the Spirit, we dare not assume that anyone who claims to be a follower of Jesus Christ is actually a Christian.
Let me put this another way: If there is not clear evidence that the old self, the sin nature, has been crucified with Christ, that the Holy Spirit has brought about a baptism of new birth, and that the person in question is now living as a new creation, then it is foolish to believe that Christ dwells within that individual.  This is not an invitation to be judgmental, nor is it any sort of works-salvation; we are absolutely and without any hesitation saved by grace alone through faith alone, but it is a reminder that we're trying to determine if someone has been transformed by the Spirit of God.  This is not something that can happen without making a difference in your life or mine, it will cause change, for the better, from the old focus on self to the new focus on selflessness.
If there is no evidence Christ-like attitudes and behaviors, then there is no Christian, its as simple as that.  Is he a Christian?  Don't tell me what he says, what does he do?  Are you a Christian, don't tell me what you think you are, how are you living your life?  For those who have been washed clean by the blood of the Lamb, there is never really any doubt, they belong to him, they've taken up their own cross and chosen to follow their savior.

If you want to delve deeper into this topic, I wrote a book about I John's perspective on the question of who is, and who is not, a Christian; it's called Christianity's Big Tent and can be accessed via that link or by going to the page at the top of this website where all of my written materials are located.