Regarding the OP's question - let me first state that every Christian should make a point of being a Biblical scholar...
I should also point out that this is hardly the first time "recognized" scholars disagree.
As some of you may know, I am ordained (I have 14 years of Baptist education in my background), and if there is one thing I truly KNOW about God's teaching it is this: it isn't up to me, this "scholar", Franklin Graham, Jerry Falwell or anyone else to tell you what to believe the Bible says. If you choose to follow Christ, its your responsibility to learn the Word of God (albeit with assistance) yourself and let the Lord move your heart to where it should be.
Personally, I strongly disagree with his assertions. However, I am of the opinion that his reaction is directly in response PURELY to the final sentence stated - the "And let’s teach them a lesson if they ever show up here." That statement DOES speak to a sense of vengeance. To "teach a lesson" using deadly force is NOT the focus of self defense, nor is it in keeping with a "purely New Testament" focus. Thus I feel that did not represent the Christian IDEAL,
However, with that said - the guy who wrote the first article has EVERY RIGHT to believe that Christians shouldn't arm themselves. I have EVERY RIGHT to believe they should. God moves the heart, and He knows us better than we know ourselves. Perhaps the writer of that article, if faced with a life or death situation - would pull a trigger to save a loved one and then live a tormented existence having committed what he mentally, emotionally and spiritually could never resolve. If that is the case, I firmly believe God would move a person like that to NOT be in a situation where that choice - if faced - would create such turmoil. For those who God knows would not lose themselves in such a situation, I do not doubt that God is perfectly (see what I did there?) fine with them being armed to defend themselves and others.
I don't have a problem with him being "wrong" in my view, and I doubt he would take issue with what he would no doubt consider an incorrect view on my part. Ultimately, we'd agree to disagree, praise the Lord for the ability to do so and remain Brothers in Christ. The Bible is full of Scripture that could be used to back one or the other position - so IF you are a Christian then I would recommend you spend some time in the Word of God and in prayer and let the Spirit move your heart to where it should be in regard to His plan for your life. If your not a Christian - well that's another discussion entirely but I will pray for you in the hope that the Lord will open your ears to His call. Then I hope He encourages you to be a RESPONSIBLE gun owner (and carrier). :lol: