1 Wakorintho 14 : 22 1st Corinthians chapter 14 verse 22

Basi, hizi lugha ni ishara, si kwao waaminio, bali kwao wasioamini lakini kuhutubu si kwa ajili yao wasioamini, bali kwa ajili yao waaminio.
soma Mlango wa 14

Therefore other languages are for a sign, not to those who believe, but to the unbelieving; but prophesying is for a sign, not to the unbelieving, but to those who believe.