Let us consider what Scripture says about tongues:
Mk 16:17-18
17 And these signs shall follow them that believe; In my name shall they cast out devils; they shall speak with new tongues;
18 .They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover.
KJV
Note that NOTHING is said about believers following after these signs!
Ac 2:3-4
3 And there appeared unto them cloven tongues like as of fire, and it sat upon each of them.
4 And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.
KJV
Note that NOTHING is said about human encouragement or instruction.
Ac 2:5-11
5 And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven.
6 Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language.
7 And they were all amazed and marvelled, saying one to another, Behold, are not all these which speak Galilaeans?
8 And how hear we every man in our own tongue, wherein we were born?
9 Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judaea, and Cappadocia, in Pontus, and Asia,
10 Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes,
11 Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God.
KJV
At first known tongues were given to fascilitate sharing the Gospel.
Ac 10:44-48
44 While Peter yet spake these words, the Holy Ghost fell on all them which heard the word.
45 And they of the circumcision which believed were astonished, as many as came with Peter, because that on the Gentiles also was poured out the gift of the Holy Ghost.
46 For they heard them speak with tongues, and magnify God. Then answered Peter,
47 Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we?
48 And he commanded them to be baptized in the name of the Lord. Then prayed they him to tarry certain days.
KJV
Here we see tongues used to persuade Jewish believers that gentiles can and do receive the same Holy Spirit as Jews do.
NOTHING is said about tongues being an essential evidence of salvation.
Ac 19:1-6
19 And it came to pass, that, while Apollos was at Corinth, Paul having passed through the upper coasts came to Ephesus: and finding certain disciples,
2 He said unto them, Have ye received the Holy Ghost since ye believed? And they said unto him, We have not so much as heard whether there be any Holy Ghost.
3 And he said unto them, Unto what then were ye baptized? And they said, Unto John's baptism.
4 Then said Paul, John verily baptized with the baptism of repentance, saying unto the people, that they should believe on him which should come after him, that is, on Christ Jesus.
5 When they heard this, they were baptized in the name of the Lord Jesus.
6 And when Paul had laid his hands upon them, the Holy Ghost came on them; and they spake with tongues, and prophesied.
KJV
Here the intent seems to be to show Pagans that the indwelling Holy Spirit brings more than belief and mental activity.
1 Co 12:7-11
7 But the manifestation of the Spirit is given to every man to profit withal.
8 For to one is given by the Spirit the word of wisdom; to another the word of knowledge by the same Spirit;
9 To another faith by the same Spirit; to another the gifts of healing by the same Spirit;
10 To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues:
11 But all these worketh that one and the selfsame Spirit, dividing to every man severally as he will.
KJV
Here the intent is to show that tongues are NOT A UNIVERSAL GIFT in the church.
1 Co 12:7-11
7 But the manifestation of the Spirit is given to every man to profit withal.
8 For to one is given by the Spirit the word of wisdom; to another the word of knowledge by the same Spirit;
9 To another faith by the same Spirit; to another the gifts of healing by the same Spirit;
10 To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues:
11 But all these worketh that one and the selfsame Spirit, dividing to every man severally as he will.
KJV
Here the intent is to reinforce the fact that tongues are NOT A UNIVERSAL GIFT in the church.
1 Co 14:5-6
5 I would that ye all spake with tongues, but rather that ye prophesied: for greater is he that prophesieth than he that speaketh with tongues, except he interpret, that the church may receive edifying.
6 Now, brethren, if I come unto you speaking with tongues, what shall I profit you, except I shall speak to you either by revelation, or by knowledge, or by prophesying, or by doctrine?
KJV
I would that ye all spake with tongues is a clear indication that it will not happen and that believers should not covet gifts they are not given.
but rather that ye prophesied is an indication that Paul considered tongues to be of lesser importance; as is verse 6.
1 Co 14:18-25
18 I thank my God, I speak with tongues more than ye all:
19 Yet in the church I had rather speak five words with my understanding, that by my voice I might teach others also, than ten thousand words in an unknown tongue.
20 Brethren, be not children in understanding: howbeit in malice be ye children, but in understanding be men.
21 In the law it is written, With men of other tongues and other lips will I speak unto this people; and yet for all that will they not hear me, saith the Lord.
22 Wherefore tongues are for a sign, not to them that believe, but to them that believe not: but prophesying serveth not for them that believe not, but for them which believe.
23 If therefore the whole church be come together into one place, and all speak with tongues, and there come in those that are unlearned, or unbelievers, will they not say that ye are mad?
24 But if all prophesy, and there come in one that believeth not, or one unlearned, he is convinced of all, he is judged of all:
25 And thus are the secrets of his heart made manifest; and so falling down on his face he will worship God, and report that God is in you of a truth.
KJV
Wherefore tongues are for a sign, not to them that believe, but to them that believe not: When we, through the Spirit, speak a language that we do not understand; it is for the benefit of the unbelieving hearer who does understand.
There is more; but enough said