It is precisely the same with all words: reality, perspectival as it is, brings certain facets of an individual to bear, bound within the resulting name or word. Collect enough of those words and interactions together, connected by a common geographic or familial series of boundaries, and you have a language—the sum total of a people’s interactions with the world capped within narrative confines. An identity. A history. That is to say, to speak Welsh is to draw forth the Welsh, Japanese the Japanese, etc. 
In light of this, I am of the opinion that using or speaking another language is to pay an ultimate respect to its people and culture of origin. One learns a language not simply to engage with others but to immerse oneself in another identity. You revere the language, and once you know it, the language’s culture is partially—permanently—subsumed into your own identity.
We see this in the Lhammas: the elves hold Valanin and Quenya  in great respect, and maintain it; learned men hold Sindarin as a language to be respected aloft. Broadly speaking, the language held in high reverence is closely associated with the people responsible for teaching the revering people. The Valar taught the elves their language, which the elves hold in regard and modified until it was their own. Early mannish tongues were influenced by the elvish language and culture, which was later modified and developed so as to be considered unique.
This is sharply contrasted with disrespectful or mocking uses of a language, which Tolkien illustrates through Melkor’s perversion of Valanin as a gift of speech to the orcs and trolls. Using a language to insult draws with it an insult to an entire people and history. Overdramatic? I think not; it is a conscious action to select a language, and draws with it the aforementioned histories and cultural implications.
I would like, too, to revisit the idea of language as an identity. We individuals hold a cradle language that undergoes development as we live. As we grow and learn, experience and think, our vocabularies and syntax develop into a roadmap of where we’ve been in our lives.  In this way, a personal vocabulary and use become reflective of, and ultimately is, an identity. Spend five minutes talking to someone; you’ll find you can tell quite a bit about their history based on the way they speak.
We can take all of this to Tolkien’s outrage in his unsent letter to Mr. Rang (297). To reiterate, there are histories behind every language that are intrinsically tied to the origins and development of the words that compose those languages. Looking far and wide for perceived “origins” due to simple auditory similarity is a deep disrespect for the pedigree of any language.
Something to consider in light of the histories that underlie the development of language: what of the Dwarves and the Valar? The Valar “had speech” from the beginning (HME 5 183) as the first of Eru Ilúvatar, and the language of the Dwarves was “derived…afresh” by their creator Aulë (ibid.). Must one consider the histories and motivations of the creators? Can those attributes actually be divined in light of the divine nature of the creators?
Additionally, we see from human history as well as from the Legendarium that languages are in constant development and flux. Using a certain language assists in the further development and enrichment of the language itself. This is relatable to the interactions between primary and secondary realities in that interacting with the secondary reality enhances the primary reality in a feedback loop as the secondary reality is further developed.
Do the names of individuals similarly influence their lines of development? Consider, for example, naming a child after a virtue (e.g. Prudence), or nicknaming a friend in light of certain interactions. Also unanswered is the nature of languages dying out; if languages are under constant development, at what point are languages considered to be separate from their forebears such that the root language is ‘discarded’?
- M. Maskeri
 This ties directly to Tolkien’s comments with respect to Sjéra Tomas Saemundsson (qtd. English and Welsh 166 as “No people in fact comes into being until it speaks a language of its own”) that languages are maintained for the sake of their people, and for the people’s identities.
 More so Ingwiquenya as the highest ‘Elvish tongue’ and record of Valanin (HME 5 188)
 Simultaneously developing a personal taste for language/aesthetic
I have no linguistic training, so I’m sorry if I’m butchering terms!