Why is speaking in tongues important in many Pentecostal churches?

In Pentecostalism, speaking in tongues—or glossolalia—is considered a vital sign of a specific religious experience known as "baptism with the Holy Spirit."1

Pentecostals believe that all Christians should seek this post-conversion experience, which mirrors the descent of the Holy Spirit upon the first Christians on the day of Pentecost. For many adherents, speaking in tongues serves as the primary evidence of this spiritual baptism. It may manifest as a personal prayer language or as a public "gift of the Spirit," one of nine supernatural gifts described by St. Paul the Apostle in the New Testament.12

Beyond its role as a sign of spiritual empowerment, the practice is deeply rooted in the belief that modern believers can and should experience the same supernatural gifts—such as prophecy, faith healing, and miracles—that were present in the early church. Consequently, it functions as a tangible connection to the divine and a demonstration of the Holy Spirit's active presence in the life of the believer.12