"For if you love them that love you, what reward have you? do not even the publicans do the same? And if you salute your brothers only, what do you more than others? do not even the publicans do so? You therefore be perfect, even as your Father which is in heaven is perfect". (Matthew 5:46-48)
Christians ought to think carefully about picking and choosing who and how they interact with while living in world and not of the world. It's been pedestrian among Christians to discriminate and blame it on God, as if He is demanding it. It's far more uncommon to carefully and prayerfully consider the admittedly complex and nuanced problems of interaction that arise in order to reflect Christ in a hedonistic culture.
Christian claims to being the undeserving recipient of Christ's unconditional service. But Christ did not classify sins when He interacted with the public. Which kinds of sinners were refused fishes and loaves? (Matthew 14:13-21, Mark 6:30-44; Luke 9:10-17; John 6:1-15) Which lepers were refused healing though only 1 returned? (Luke 17:11-19) Was the woman at the well refused water? (John 4:5-42)
Christ used lesser blessings (i.e. food and water) to create opportunity (among other things) to speak of greater blessings (i.e. Word and Water). Some drew nearer to Christ, some continued in compliant company, and some walked away. Can a Christian claim Christ's righteousness and discriminate in public interactions? To refuse lesser blessings after having received the greater blessings in Christ might be the more egregious sin.
I grant that there is no 'one size fits all' answer. That's the point, it requires a careful and prayerful stance to reflect Christ rather than your own biases. A Christian fleeing away from sin and sinners due to bias admits a serious flaw in his or her understanding of sin and sinners. The real danger is not a Christian living in the sinful world, but a world of sin living in a Christian. Wherever you go sinner, there you are.
