Here's what caught my attention: "The men traveling with Saul stood there speechless; they heard the sound but did not see anyone" (Acts 9:7). Later in Acts 22:9, Paul recounts the story and gives us a little more detail. Paul's companions heard the voice but did not understand it. This is an awful lot like John 12:29; the people heard the audible voice of the Father but did not understand it. They did not have ears to hear.
This begs the question: what is the role of experience in faith? For Paul the experience he had on the road to Damascus changed everything; it changed his understand of Scripture and his view of the nature of God. Before encountering Christ, people could have argued with Paul until they were blue in the face and he still would have strung them up. When we meet the risen Lord in a tangible way the experience provides a monument in the life of the faith. In our hearts, we pile 12 stones on top of each other to remind ourselves of what God has done. This was real. It happened. God met me here.
Many of the great men and women of the faith who have gone before mention the central role experience played in their life of faith. Blaise Pascal wrote his down on a sheet of paper and sewed it into his coat. We have no clue what it was--he never tells. We only know that when doubts battered his faith, he would rip open the stitching on his coat, take out the piece of paper and read it to himself. This was real. I don't know how to answer all the questions coming at me right now but I do know this event happened. You cannot argue with an experience. Paul says "God knocked me off my horse and you want to argue that He's a figment of my imagination?".
Paul's companions are a different story. Nowhere do we read about their interpretation of events. Paul lets us know in a single sentence they didn't get it. They were present for the experience but they were not participants in the experience.
This has a couple of applications for teaching on the Holy Spirit. First, it is completely inappropriate for someone to take their experience of God and shove it onto someone else. The "did you feel that?" type questions are fine, but there cannot be an expectation in the group that everyone will be affected in the same way. Second, we cannot discount someone else's experience just because we didn't have one. Paul says "I heard the audible voice of God!" and his companions say "Whatever Paul, it only thundered."
Spirit, give us eyes to see and ears to hear.