I think neals meant "modern" Christianity, as in what has become of Christianity thanks to the age of reason. This excludes some Western (especially US) branches of Christianity.
“You have heard that it was said, ‘An eye for an eye and a tooth for a tooth.’ But I say to you, Do not resist the one who is evil. But if anyone slaps you on the right cheek, turn to him the other also. - Matthew 5:38-39 ESV
http://www.amazon.com/Nonviolence-History-Dangerous-Mark-Kur...