How Christians Are Supposed to Act as Members of a Community

Each of us must consider his neighbour’s good, so that we support one another. Christ did not indulge his own feelings, either; indeed, as scripture says: The insults of those who insult you fall on me. And all these things which were written so long ago were written so that we, learning perseverance and the encouragement which the scriptures give, should have hope. (Rom. 15:2-4)

Selfishness is not a Christian virtue.  Selfishness is just a sin.