Speaking in tongues and preaching in another language are two different things.
For he that speaketh in an unknown tongue speaketh not unto men, but unto God: for no man understandeth him; howbeit in the spirit he speaketh mysteries. - 1 Corintheans 14:2
You have proven nothing with this reference. I could say exactly the same thing about me speaking Japanese in a church where no one understood it. I would be speaking mysteries, and I would be doing it in the spirit, meaning in a spiritual way if I were talking about spiritual things.
Prove to me that "speaking in tongues" in the Bible means what you say it is and not what I say it is. I have plenty of evidence on my side that the Bible word "tongue" simply means "language."
Here is just one example from the Friberg lexicon entry for
glossa. Note that the typical Charismatic meaning of making sounds you don't know the meaning of is not in the lexicon. I have omitted the Greek words in the definition since they don't transfer to the BB.
"glossa: the tongue, Hom., etc.
2. the tongue, as the organ of speech, through love of talking, Hes., Aesch.; by word of mouth, Hdt., Thuc.; not by word of mouth, not from mere hearsay, Aesch.; so, Soph.; i`e, to let loose one's tongue, speak without restraint, Id.; pl., i.e. with blasphemies, Id.:-for
II. a tongue, language, Hom., Hdt., etc.
III. the tongue or mouthpiece of a pipe, Aeschin. (Deriv. unknown.)"