Anytime you come across words like "authentic", "true", or "real" in conjunction with any religion you can assume that what follows will be complete bull shit. A recent post by Roger E. Olson, "Why Authentic Christians Must Oppose the Death Penalty", is no exception. In fact, it's a pretty blatant example. Jesus is not a good figure to go back to when trying to come up with a poster boy for the abolition of the death penalty. There are numerous passages where the Jesus figure shows himself to be temperamental and at times a homicidal asshole. One of my favorite passages in this regard is Luke 19:27
"But those mine enemies, which would not that I should reign over them, bring hither, and slay them before me."
I have yet to hear a reasonable explanation as to how this could mean anything other than a direct command from Jesus to his followers to round up and massacre all non-followers. Call me crazy, but commanding mass murder seems rather antithetical to abolishing the death penalty.
The truth of the matter is that "real" Christians can pretty much behave any fucking way they want since their religion is so convoluted and contradictory that it can be interpreted in just about anyway the imagination wants. That goes for every religion I've ever come across.