Last week we had a discussion at work about whether the Christian ethic is inconsistent or not. Moses said, "Eye for an eye" and Jesus said, "Turn the other cheek." But Jesus endorsed the law of Moses.
I've always regarded apparent contradictions as an opportunity to learn. These are generally resolved by finding distinctions. And one learns as one finds distinctions. (If you know how to distinguish between Monza Red and Candy Apple Red, you've learned something about cars.)
Resolving the "eye for an eye" versus "turn the other cheek" problem involves distinguishing between large injuries and small injuries. There's an old saying that, "it's all fun and games until someone loses an eye." If you're messing with a Red Ryder BB gun and someone puts an eye out with that thing, it's a big deal. You should get into legal trouble if it wasn't an accident.
But not every injury rises to that level. There's a popular book entitled, "Don't sweat the small stuff." When Jesus says to turn the other cheek, he's talking about a small thing that's best not blown all out of proportion. The Romans had a law that said that a Judean could be forced to carry a Legionaire's gear one mile. Jesus told people to go the extra mile. If everybody is doing more than what's required of them in a million small ways, society will get along better. I think of this as social lubricant.
Thou shalt cut the other guy some slack, give him the benefit of the doubt. We are imperfect beings who work with partial knowledge. Jesus's ethic of social lubricant provides a coping mechanism for this.
I once told someone this and she said, "Does this mean I should be a doormat?" And I replied, "No, sometimes you run out of doubt." There are times when there is no doubt that a crime has been committed. There are times when whatever social framework within which you find yourself, e.g. the laws of the state of Michigan, specifies sanctions and punishments for specific misdeeds. In those cases, you pursue justice.
The Christian exists in tension of Mercy and Justice. We care about right and wrong, so we recognize and we embrace Justice. But we acknowledge we're sinners and we seek Mercy.
So, where do you draw the line between small things that you make a point of mercifully letting things slide versus large things where you pursue justice? It depends upon you. Jesus said that the same strictness by which you judge others will be the strictness by which you will be judged.