Here's a little tip to our agnostic and atheist friends when talking about religious books. Be prepared to cite the verses that support your position if you want people to take it seriously. The verses below explain that Christians are only called to separate themselves from those who call themselves followers of Jesus yet don't live the message. It's an example of church discipline.
1 Corinthian 5:
9I have written you in my letter not to associate with sexually immoral people
10not at all meaning the people of this world who are immoral, or the greedy and swindlers, or idolaters. In that case you would have to leave this world.
11But now I am writing you that you must not associate with anyone who calls himself a brother but is sexually immoral or greedy, an idolater or a slanderer, a drunkard or a swindler. With such a man do not even eat.
Christians are called to take the opposite stance with nonbelievers
Romans 12:
17Do not repay anyone evil for evil. Be careful to do what is right in the eyes of everybody.
18If it is possible, as far as it depends on you, live at peace with everyone.
19Do not take revenge, my friends, but leave room for Gods wrath, for it is written: It is mine to avenge; I will repay,
d says the Lord.
20On the contrary:
If your enemy is hungry, feed him;
if he is thirsty, give him something to drink.
In doing this, you will heap burning coals on his head.
e
21Do not be overcome by evil, but overcome evil with good