Yes, I'm familiar with the eye for an eye concept. It's the basis of our tort system, which provides for monetary compensation for damages.
What is your point.
You have two issues. First an eye for an eye is rejected in the scripture quoted. Secondly, if the gospel of Jesus Christ is not based upon christian principle, then what?
My point? America didn't fight the revolutionary war while turning the other cheek to the brits. A foundation of the gospel of Christ as quoted by matthew is to love thy enemy as thyself and to turn the other cheek for him to smite thee yet again.
Fighting the revolutionary war was hardly the "christian" thing to do.
Perhaps there is a time where Jesus said his followers are permitted to stand up to and slaughter their enemies?
Too many mixed signals I guess.