Most of your post is hard to follow and mixes a lot of topics. On the issue whether pain and social rejection have something in common, a highly-cited fMRI study [found](https://10.1126/science.1089134) that 

> In summary, a pattern of activations very
similar to those found in studies of physical
pain emerged during social exclusion, providing
evidence that the experience and regulation
of social and physical pain share a
common neuroanatomical basis.

Likewise a [newer study](http://www.pnas.org/content/108/15/6270) concludes that:

> rejection
and physical pain are similar not only in that they are both
distressing—they share a common somatosensory representation
as well.

An even more recent study has [challenged these](https://www.nature.com/articles/ncomms6380) though:

> Pain- and rejection-related representations are uncorrelated within regions thought to encode pain affect (for example, dorsal anterior cingulate) and show distinct functional connectivity with other regions in a separate resting-state data set (N=91). These findings demonstrate that separate representations underlie pain and rejection despite common fMRI activity at the gross anatomical level. Rather than co-opting pain circuitry, rejection involves distinct affective representations in humans.

Since most of the "hurtful" words on SE are of the kind that lead the receiver to experience some level of exclusion (not being "good enough" to be part of the site[s] etc.)... it seemed appropriate to mention this. Of course you can make someone feel excluded while being perfectly polite.

----

I'm less familiar with research on the effects of verbal abuse, but at least [one study found](https://ajp.psychiatryonline.org/doi/full/10.1176/ajp.2006.163.6.993) it has long-term negative consequences for some children. In fact there's [more than one](https://www.fsu.edu/news/2006/05/22/invisible.scars/) study with the same conclusions.

I don't know if there are studies on the extent to which adults are just able to shrug off verbal abuse. But there certainly are books arguing for not tolerating it in the workplace, e.g. Bob Sutton's ["No asshole"](https://en.wikipedia.org/wiki/The_No_Asshole_Rule) series.

And despite what your Polish Zen psychologists would like the reality to be, it just doesn't work like that in practice. Verbal abuse does have some effect, even on people (e.g. nurses) who encounter it often. Granted the effect is not huge. On a scale of 0 (no reaction) to 6 (extreme feeling), the average effects of verbal abuse are reported below:

[![enter image description here][1]][1]

There are a lot more studies on the effects bullying, which combines verbal abuse with other behaviors. Actually a problem with work-related constructs including verbal abuse is that there's perhaps a bit too many of them. But there's a slightly narrower one that was studied namely incivility; from [Hershcovis (2011) ](https://doi.org/10.1002/job.689):

> Incivility has recently emerged as one of the most studied variables in the workplace mistreatment [long list of citations]. It was defined by
Andersson and Pearson (1999) as low intensity deviant acts such as rude and discourteous verbal and
non-verbal behaviors enacted toward another organizational member with ambiguous intent to harm.
This construct differentiates itself from other constructs on several dimensions. First, it is defined as a
low intensity behavior. Andersson and Pearson explicitly argue that minor forms of mistreatment can
have a significant impact on employee attitudes toward the organization. In contrast, most other
mistreatment constructs are not defined in terms of their intensity, though intensity may be inferred by
their definition or measurement. For example, bullying can be assumed to be of higher intensity than
incivility because of its persistence and frequency.
A second differentiating feature of incivility is the explicit statement that intent is ambiguous.
Researchers in the workplace mistreatment literature have frequently debated the notion of intent. For
instance, Neuman and Baron (2005) argued that when defining mistreatment from the perspective of
the actor, intent is crucial. Otherwise, accidentally harmful behaviors such as being hurt by a dentist
during a dental procedure may be considered aggressive. On the other hand, from a target’s perspective,
perceived intent may be all that matters because victims will react based on their perception, whether or
not their perception is accurate. 

Nonetheless, the effects of incivility were comparable with that of bullying in a work environment:

[![enter image description here][2]][2]

[Infante (2009)](https://doi.org/10.1080/03634529509378997) points out that the negative effects of verbal aggresion have been seen in multiple contexts:

>Verbal aggression is message behavior which attacks a person's self-concept in
order to deliver psychological pain (Infante & Wigley, 1986). Researchers in
recent years have given considerable attention to verbal aggression in numerous
contexts such as interpersonal, family, organizational, political, and intercultural.
This research has been unequivocal in suggesting that verbal aggression is
a highly destructive form of communication. For instance, it can result in violent
crimes (Toch, 1969; Zillmann, 1979), it is a catalyst to interspousal violence
(Infante, Chandler, & Rudd, 1989), it is associated with adolescents having
problems when they are the victims of their parents' verbal aggression (Straus,
Sweet, & Vissing, 1989), and it is a very negative factor in superior-subordinate
communication (Infante & Gorden, 1991).  [...]

> The types of verbally aggressive messages, derived deductively from theory
and research, are: character attacks, competence attacks, background attacks,
physical appearance attacks, maledictions, teasing, swearing, ridicule, threats,
nonverbal emblems (Infante, 1987). However, other types also can be specified:
blame, personality attacks, commands, global rejection, discontinuation, negative
comparison, sexual harassment, and attacking the target's significant others.

> Continuation of verbal aggression after it is initiated, largely is due to reciprocity. People often feel compelled to return acts of aggression to save face
and to discourage future attacks (Felson, 1978, 1982). Reciprocating verbal
aggression can escalate tensions to the point of physical aggression (Berkowitz,
1962, 1973). Even if reciprocity does not result in violence the destructiveness
nevertheless is more than what would have occurred had one party not
reciprocated.

I.e. a tit-for-tat exchange or verbal aggression can result is what is nowadays 
more colloquially called a "toxic environment".

> The
research has focused on effects of verbal aggression in different communication
contexts. Two basic effects are self-concept damage and aggression escalation.
These can lead to reduced trust, relationship deterioration, and relationship
termination in interpersonal communication. Organizational communication
research has found that the verbally aggressive behavior of supervisors has
negative effects (Infante & Gorden, 1985, 1987, 1991). Verbally aggressive
subordinates are evaluated unfavorably by their supervisors (Gorden, Infante,
& Izzo, 1988; Infante & Gorden, 1989). Family communication research has
suggested that children may be harmed by their parents' verbal aggression
(Straus et al., 1989). Other research suggests husbands of verbally aggressive
wives are more depressed (Segrin & Fitzpatrick, 1992). Verbal aggression in a
marriage is negatively related to marital satisfaction (Payne & Sabourin, 1990;
Rancer, Baukus, & Amato, 1986). Several studies indicate verbal aggression
sometimes leads to interspousal violence (Gelles, 1974; Infante et al., 1989;
Straus, 1974). The use of verbal aggression in political communication has
negative effects on source credibility (Downs, Kaid, & Ragan, 1990). A study
which manipulated verbal aggression in an experiment suggests that the relationship
with lowered source credibility is causal (Infante, Hartley, Martin, Higgins,
Bruning, & Hur, 1992).
It should be emphasized that the results of research have been remarkably
consistent in suggesting that the effects of verbal aggression are negative,
supporting the ethical stance that verbal aggression is a destructive form of
communication that should be discouraged.

Infante also discusses mitigation strategies, although the existence of these doesn't justify your point that verbal aggression is harmless:

> Once verbal aggression does occur in a situation, basic concerns are how the
effects can be neutralized and how escalation of aggression can be prevented. [...]

> [An] approach is based on symbolic interactionism and involves the
strategies that victims may use to "dismiss" verbal attacks or render them
ineffective (Wagner, 1980). Protecting self from abuse by manipulating symbols,
according to this view, is one of the most highly developed functions of our
symbol system. Wagner (1980) conceives of these as "strategies of dismissal." He
presents numerous strategies that the victim of an attack can use while interacting
with the attacker or while interacting with self in order to restore the
attacked self to a state of equilibrium. Some of these strategies are reviewed
below (see Wagner, 1980, for a more complete discussion).

> Many dismissals of an attack rely upon finding an exception to the locus of
attack. These can pertain to the situation of the attack, the victim, or the attacker.
Dismissal strategies for the situation invoke misinformation (claim that the attack
was based on incorrect information) or coercion (contend that the data which
attacks self s judgment was obtained by coercion). Dismissals based on the victim
involve one's conception of self and utilize the idea that the object of attack was
not the "true" self. Some of these strategies are personal growth (maintain that the
self characterized in the attack no longer exists because of change), the unconscious
(agreeing with the unfavorable characterization by the attacker but
claiming the matter is beyond personal control because the unconscious mind is
responsible), and excuse (claim the behavior which suggests an undesirable self
"was not my fault"). Strategies that focus on the attacker seek to derogate the
source. These are based on ignorance (the attacker does not know what he/she is
talking about), the dark side (the attack was motivated by lesser human tendencies
to be jealous, envious, resentful, vicious, sadistic), and unacknowledged motives
(the attacker has a hidden agenda).
These strategies of "dismissal" seem aimed mainly at neutralizing the effect of
verbally aggressive remarks so that the victim does not experience a sense of
dissonance with self. This can be done to a considerable extent at the intrapersonal
level.

Unlike your Christian-motivated book, Infante doesn't try to order these strategies. And these are just the purely self-oriented strategies. He spends even more space discussing (non-aggressive) communicative response strategies.


  [1]: https://i.sstatic.net/DOhXP.png
  [2]: https://i.sstatic.net/1oWWi.png