Is it appropriate for Christians to insult non-believers or heretics because Jesus insulted the pharisees or because the church fathers insulted the heretics of their time? Are we wrong nowadays to be respectful in our dialogues with people of other views, even those claiming to be Christian who we believe represent a false view? I always felt it was a sign of Christian charity that those in the Christian spectrum were more capable of holding civil discourses than secular humanists, who are often arrogant, carnal and cold. I wonder because I had been insulted for my errors by other professing Christians and I sometimes question whether it was appropriate or just done out of pride and cruelty. I've always believed a compassionate response and interaction produces the best fruit. Christians from what I understand are supposed to be slow to anger, even when the faith is being attacked. But I saw an Orthodox blog making some really nasty remarks to a Roman Catholic writer that seemed carnal, but he used the church fathers to justify this behavior. Likewise, I've seen the same hostility from Romans towards Lutherans, and other denominations. Protestants also to others, of course.
The harsh language - even name-calling - really seemed to come out towards false brethren rather than blantant non-believers. John the B. and Jesus against the pharisees (who were supposed to be faithful to the true God but weren't), Paul against the Judaizers, other Fathers against the heretics, Luther against, err, lots of people... that's where the harshest language tends to come up. The impact of insulting a pagan in a debate would be less, considering they're not on board with the truth at all. By temperament, I am quite averse to name-calling and strong language; I don't find much use for ad hominem and mockery. And although I do enjoy a good satire from time to time, I would think thrice before utilizing it in the pulpit or hypothetical debate hall. If you can't say something calmly and reasonably, don't bother saying it at all. (I can't abide preachers who shout, for the same reason.) But if the Spotless One could call people a brood of vipers and children of the devil, I guess sinless wrath is technically possible...
I heard this argument used at an abusive and very hypocritical apologetics forum. They'd use it as an excuse to indulge their carnality. Every single opportunity to exercise their cruelty was given on account of this. They had a very cult-like mentality where they gave you the impression they were the only ones who did things right and all the generosity shown by the more fruit-bearing humble Christians was a fraud. They believed it was more humble to believe in biblical errancy because it was more in touch with modern times, using terrible arguments that had adequate resolutions (I assume because if you leave a door open for errancy in scripture, you can give a foothold to reject other parts you don't like more easily), held to a lot of post-modern political views that were not reconcillable with scripture just to appear 'counter cultural', had a lot of rude and impious humor, a very inconsistent standard of criticism when picking others apart, and a disturbing ambition to spread their cancer to the internet at large. The two notable apologists of this community, known as TheologyWeb, were JP Holding of Tektonics and Nick Peters of Deeper Waters. Both were calloused and cruel, hated by all and fiercely loyal to the cult. They always talked about how important the trinity and resurrection were to Christianity but their behavior was repelling to many. They were mostly preaching to the choir, and TWeb had a serious lack of success in gaining converts overall, unlike the more humble, traditional apologists. After suffering mental abuse by the members while desperately seeking help in the midst of spiritual anguish and doubt, I managed to break away from the community. I prayed, at first for vengeance, but then tried to remain humble and ask that the wolves be driven out and those who still had some potential to do good would repent and use their gifts for good, and that the site would disappear in some way or another or be stifled from influencing the rest of the world. I eventually learned around 2014 that the site, shortly after I left and prayed, had lost their entire decade-long history in a massive hard drive crash with no backups except the most recent ones that year, and everything else had vanished. Several ardent members left the community to pursue other interests, some taking on a more radical disposition or adopting heretical views, a few even abandoning the faith, and that JP and Nick left the site to pursue their own work separately. And while JP and Peters still defend some rather liberal, erroneous postmodern views, they eventually cleaned up a lot of their contributions and work to remove the demeaning and mocking tone it once had. I consider it the work of God in some way. I hope they continue to grow out of their errors and see the light, as all of us should. When I look back, I realize how little TheologyWeb taught me about theology. They had some very superficial arguments for some of the bigger aspects of the Christian faith I mentioned, like the resurrection, but nothing that hadn't been explained just as well elsewhere, with all the errors and liberal 'scholarship' excised. I am still angry when I remember the things people did and said to me there, and am mad at myself for falling into the snare and becoming addicted to it so as to allow myself to be abused, but it was a hard lesson to learn. A lot of internet apologists are spreading heresy and liberalism, trying to pass it off under a kind of psuedo-orthodoxy, and it's doing a lot of damage when a lot has to be done in this day and age to defend Christianity from an accurate point of view.
I would say that it is proper to strongly criticize heretical clergy who are leading their faithful astray, for example, some of the false-Anglican priests who are working to destroy the Episcopal Church in the US, and other Anglican provinces, and likewise equivalent malfeasant pastors in other denominations. Heresiarchs, in other words. John Shelby Spong comes to mind. It is also legitimate to polemically criticize other religions, especially new religious movements and cults like Scientology, the Moonies, the Unitarian Universalists, Mormons, New Atheists, Jehovah’s Witnesses and so on who are actively proselytizing Christians, in order to discourage Christians from falling into them. But one must be careful. Dialogue with other religions has taken on a more respectful tone; I, for example, have no desire to get into an argument with a Sikh, a Taoist or a Zoroastrian, or especially a Jew, about their religion, but rather have a level of mutual respect. Most missionaries and evangelists know that it is pointless to try to convert someone to Christianity by debating with them. Rather, Christianity should be majestically but not offensively presented, and every loving welcome given that is not excessively familiar, or to use the modern vernacular, “touchy-feely-squeezy,” or “love bombing”, in a respectful manner, to those who come to us. The idea must be to pull rather than push; consider how annoying Jehovah’s Witnessses missionaries are; they are doing it exactly the wrong way. But on that note, we should not insult or abuse anyone, even heresiarchs, and especially, we should refrain from insulting or abusing the lay members of other religions. That is because this is un-Christian snobbery, and it will cause these people to resent us rather than desire to convert. It sets a terrible example. And here, I have a confession to make: I have gotten into the dreadful habit of referring to Mormons behind their backs as “Mormonics.” This is something I need to stop doing, because if a Mormon heard me talking that way, it could destroy a friendship or put them off to Christianity. And I have a very close friend who did unfortunately convert to Mormonism.
And I also feel deep remorse for possibly insulting any Roman Catholics who were among the generous exceptions to the hurtful ones I've had many unfortunate encounters with.
I agree with you in one way, but I do think that there is some merit in the way they go about it all. So often nowadays, myself included, we will criticise those who preach in the markets and towns upon pedestals, and those who go round knocking on people's doors, but at least they're doing something proactively. There are better, more effective, ways of evangelising people, but I certainly think that type of thing has its place. In our reaction against it (door-to-door preaching and the like) we have almost went too far the other way, in my opinion. That's my take on things here in Britain, anyway, I imagine things could be quite different in the USA, for example. Edit: Maybe I'm not making the distinction between door-to-door preaching and "open air" preaching actually. I tend to lump them all together as the same "type", if you will, which is perhaps wrong of me.
I think the door to door type is specifically wrong, because it is an inconvenience to people, an imposition, a disruption of privacy, whereas conversely the public preaching is a legitimate use of freedom of speech. Except to the disturbing extent where in the UK, a street preacher was prosecuted and indeed persecuted for preaching against homosexuality, in the early 2000s. I cannot recall how that case turned out.