John Calvin Commentary 1 Corinthians 14:39

"Wherefore, my brethren, desire earnestly to prophesy, and forbid not to speak with tongues." — 1 Corinthians 14:39 (ASV)

Wherefore, brethren, this is the conclusion in connection with the principal question—that prophecy is to be preferred to other gifts because it is the most useful gift of all, while at the same time other gifts should not be despised.

We must observe, however, his manner of speaking. For he intimates that prophecy is worthy of being eagerly and ardently aspired to by all. In the meantime, he exhorts them not to envy others the rarer gift, which is less to be desired; indeed, to give them the praise they are due, setting aside all envy.