Speaking in tongues — is it the unique initial evidence that someone has been baptized with the Holy Spirit? Or should we look for another sign?
Pentecostal Christianity worldwide is believed by some researchers to number half a billion members. The vast majority of them strongly hold the doctrinal position that a person baptized with the Holy Spirit will speak in tongues as the initial evidence of that experience. That is the position that will be put forth in this bible study. Let’s examine three primary Scripture portions that lead to this conclusion.
Acts 1:4-5; 2:1-4 On one occasion, while he was eating with them, he gave them this command: “Do not leave Jerusalem, but wait for the gift my Father promised, which you have heard me speak about.  For John baptized with water, but in a few days you will be baptized with the Holy Spirit.” ... [2:1] When the day of Pentecost came, they were all together in one place.  Suddenly a sound like the blowing of a violent wind came from heaven and filled the whole house where they were sitting.  They saw what seemed to be tongues of fire that separated and came to rest on each of them.  All of them were filled with the Holy Spirit and began to speak in other tongues as the Spirit enabled them.
•• What is unique here? — the speaking in other tongues. Glossolalia is the technical term used by theologians to describe this experience.
•• What is not unique here? — the manifestations of wind and fire.
• 1 Kings 19:11 The LORD said [to Elijah], “Go out and stand on the mountain in the presence of the LORD, for the LORD is about to pass by.” Then a great and powerful wind tore the mountains apart and shattered the rocks before the LORD, but the LORD was not in the wind.
• 1 Kings 19:12a After the earthquake came a fire, but the LORD was not in the fire.
• 1 Kings 19:12b And after the fire came a gentle whisper [KJV: a still small voice]. It was in the voice, the speaking, that Elijah discerned the Lord. So he went out to the mouth of the cave to meet with the Lord who spoke to him.
•• Elijah met with God at Mount Horeb. God granted him dramatic manifestations of wind and fire, also an earthquake. But the bible specifically states that “the Lord was not in the wind ... not in the fire.” Elijah sensed the Lord in the “still small voice.”
•• At Pentecost in Acts 2:1-4, the disciples likewise experienced dramatic, God-sent manifestations of wind and fire — similar to Elijah at Mt. Horeb. But the only unique manifestation on that day of Pentecost was the talking in tongues, not the wind and fire.
Acts 10:44-46 While Peter was still speaking these words, the Holy Spirit came on all who heard the message.  The circumcised believers who had come with Peter were astonished that the gift of the Holy Spirit had been poured out even on the Gentiles.  For they heard them speaking in tongues and praising God.
•• What was not unique here? — the praising of God, which is common throughout the Old and New Testaments.
Acts 19:6 When Paul placed his hands on them, the Holy Spirit came on them, and they spoke in tongues and prophesied.
•• Once more, what was unique here? — the speaking in tongues.
•• What was not unique here? — the prophesying, which is commonly seen in both Testaments.
The Scriptural conclusion? The baptism with the Holy Spirit (as we have seen in Acts 2, 10, and 19) is a uniquely New Testament experience. And it has a unique initial evidence — speaking in tongues!
The sound of a rushing, mighty wind (Acts 2:2) is not an evidence, nor is it “the evidence”. It occurred on only one of the New Testament instances of the baptism of the Holy Spirit. And it had occurred in the Old Testament (e.g., 1 Kings 19:11), where it was clearly not the evidence of the Pentecostal baptism with the Spirit.
Fire, or tongues of fire (Acts 2:3), is not an evidence, nor is it “the evidence” of the Holy Ghost baptism. It also occurred in only one of the New Testament cases. And fire was a fairly common occurrence in the Old Testament when God revealed Himself, and again clearly not in the context of the Holy Spirit baptism.
Praising God (Acts 10:46) is universal throughout Scripture. So it cannot be singled out as an evidence that one is Spirit-filled. Many non-Spirit-filled people praised God in the Old Testament and continue to do so today.
Prophecy (Acts 19:6) is likewise common in the Old Testament among those not baptized in the Holy Spirit in the abiding, Acts 2, Pentecostal way. So it too cannot be put forth as a unique evidence that one has received the baptism of the Spirit.
What conclusions can be drawn from the Scriptures we have examined?
• Neither wind nor fire are necessary evidences of the baptism with the Holy Spirit.
• And if they do occur, as they already had in the Old Testament, they do not therefore uniquely certify that the person has received the Holy Spirit baptism.
• Neither praise nor prophecy is a necessary evidence. They may indeed occur, but many Old Testament persons did one or both, but were not baptized in the Spirit.
• Other things — like love, or renewed zeal — may flow from the baptism with the Holy Spirit. But they also characterize many Old Testament saints without this Pentecostal, spiritual filling.
• Only speaking in tongues (as in Acts 2, Acts 10, and Acts 19) is the unique evidence of the unique New Testament experience called the baptism with the Holy Spirit.