Acts 2:6
When they heard this sound, a crowd came together in bewilderment, because each one heard them speaking in his own language — the crowd's confusion (syneggisen, confused) is the inverse of Pentecost's purpose: understanding is restored. Each hearing their own language (idia dialektos, native tongue/dialect) is the miracle; not that one person speaks many languages, but many people hear one message in their own idiom. This is Gospel accessibility and God's respect for human particularity.