John Calvin on 1 Corinthians 14:13

13. Wherefore let him that speaketh in another tongue This is an anticipation, by way of reply to a question which might very readily be proposed to him. “If any one, therefore, is able to speak a foreign language, will the gift be useless? Why should that be kept back, which might be brought out to light, to the glory of God?” He shows the remedy. “Let him,” says he, “ask from God the gift of interpretation also. If he is without this, let him abstain in the meantime from ostentation.” “De parler a ostentation;” — “From speaking for ostentation’s sake.”