“Says Paul: ‘Brethren, be not children in understanding!’ Here, continues Barnes, it is as if Paul had said: “Your admiration of a foreign language, and of the ability to speak it, is of as little solid value as the common sports and plays [or games] of boys!”
Indeed, explains Barnes: “The meaning may be thus expressed. ‘Your admiration of foreign languages is like the sports and plays of childhood. In this respect, be not children (paidia). Be men! Lay aside such childish things! Act worthy of the understanding which God has given you!'”
Paraphrase of I Corinthians 14:21-22
Continues Paul: “In the Law, it has been written that ‘I will speak to this people [of Israel] with other languages, and with other lips [or ‘with the lips of other peoples’ such as the Assyrians]! Yet, even then, they [the Israelites] will not listen to Me!’ — says the Lord.”