The day of Pentecost marked the birthday of the church, with 120 people filled with the Holy Spirit and speaking in known languages to get the attention of outsiders. This event is an atypical, non-repeatable occurrence, where the Holy Spirit gave gifts to believers, including prophecy, healing, and miracle working. The gift of tongues in Acts 2 is different from the gift of tongues in 1 Corinthians 14, with the former being understandable languages and the latter being unable to understand without a special gift of interpretation.
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