¹⁹ nevertheless, in public worship I would rather say five understandable words in order to instruct others, than ten thousand words in a tongue [which others cannot understand].

Instruction for the Church

²⁰ Brothers and sisters, do not be children [immature, childlike] in your thinking; be infants in [matters of] evil [completely innocent and inexperienced], but in your minds be mature [adults]. ²¹ It is written in the Law, “By men of strange tongues and by the lips of foreigners I will speak to this people, and not even then will they listen to Me,” says the Lord.^{(A) 22} Therefore, [unknown] tongues are [meant] for a [supernatural] sign, not to believers but to unbelievers [who might be receptive]; while prophecy [foretelling the future, speaking a new message from God to the people] is not for unbelievers but for believers.