Here's my definition of a "christian"....one who practices "love" in this way. Corinthians 1:13
1 If I speak in the tongues [a] of men and of angels, but have not love, I am only a resounding gong or a clanging cymbal. 2 If I have the gift of prophecy and can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but have not love, I am nothing. 3 If I give all I possess to the poor and surrender my body to the flames, [b] but have not love, I gain nothing.
4 Love is patient, love is kind. It does not envy, it does not boast, it is not proud. 5 It is not rude, it is not self-seeking, it is not easily angered, it keeps no record of wrongs. 6 Love does not delight in evil but rejoices with the truth. 7 It always protects, always trusts, always hopes, always perseveres.
8 Love never fails. But where there are prophecies, they will cease; where there are tongues, they will be stilled; where there is knowledge, it will pass away. 9 For we know in part and we prophesy in part, 10 but when perfection comes, the imperfect disappears. 11 When I was a child, I talked like a child, I thought like a child, I reasoned like a child. When I became a man, I put childish ways behind me. 12 Now we see but a poor reflection as in a mirror; then we shall see face to face. Now I know in part; then I shall know fully, even as I am fully known.
13 And now these three remain: faith, hope and love. But the greatest of these is love.
Anyone living life in this way....deserves to be called a Christian.