"Tongues" of PENTECOST: Glossolalia or Xenoglossia?

"The original gift of tongues was the power to preach the gospel fluently in a language that the speaker had never learned or known in any way.

xenoglossia “speaking in tongues” —that is, speaking in a language

which one has never learned or known.
Note —The term xenoglossia is defined in Chambers’s dictionary as
“the spontaneous use of a language which the speaker has never heard or learned.” From Greek, xeno strange, glossa tongue.
This phenomena, which can rightly be described as “the gift of tongues”, is the ability to speak fluently a language one has never studied, had any exposure to, or “known” in any natural sense.

glossolalia “ecstatic utterances” —that is, uttering language-like but unintelligible sounds usually in a state of elation.
Note —The term “glossolalia” is defined in Chambers’s dictionary as “the phenomena of spontaneously uttering unintelligible sounds believed to form part of an unknown language or languages.” 

From Greek, glossa tongue, laleein to talk.
There are two components to this phenomena, neither of which is
miraculous.
Utterance of language-like sounds. There is nothing extraordinary

about this. Even children, before they speak a real language, chatter away in imitation of language, yet unintelligibly. Anybody can do this.
Ecstasy, trance-like elation. There is nothing extraordinary about this either. It is harder to do on purpose than the first component, however anybody can do it without using drugs.

Now let us examine the Biblical description of "speaking in tongues" to see which, if any, of these two phenomena match that description.

The true Pentecostal tongues, spoken by the apostles, are described by the very people who heard them: 

"We each hear in our own language in which we were born." 

Acts 2:8 NKJV

In church I would rather speak five words with my mind in order to instruct others, than ten thousand words in a tongue...

---Tongues are a sign not for believers

but for unbelievers,

---while prophecy is a sign not for unbelievers

but for believers.

1 Corinthians 14:19,22 CSB."
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