Deuteronomy 28:49

49 aThe Lord will bring a nation against you from far away, from the end of the earth, bswooping down like the eagle, a nation cwhose language you do not understand,

Psalms 114:1

Tremble at the Presence of the Lord

1 When dIsrael went out from Egypt,
the house of Jacob from ea people of strange language,

Isaiah 28:11

11 fFor by people of strange lips
and with a foreign tongue
the Lord will speak to this people,

Jeremiah 5:15

15 gBehold, I am bringing against you
a nation from afar, O house of Israel,

declares the Lord.
It is an enduring nation;
it is an ancient nation,
a nation whose language you do not know,
hnor can you understand what they say.

1 Corinthians 14:21-22

21 iIn the Law it is written, jBy people of strange tongues and by the lips of foreigners will I speak to this people, and even then they will not listen to me, says the Lord.” 22Thus tongues are a sign not for believers but for unbelievers, while prophecy is a sign
Greek lacks  a sign
not for unbelievers but for believers.
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