And they were all filled with the Holy Spirit and began to speak with other tongues, as the Spirit gave them utterance.
A sign to a healthy church is a church that believes in, teaches, and leads others into receiving the promise of the Father, which is being filled with the Holy Spirit with the evidence of speaking in tongues. This promise spoken of by Jesus in Acts 1:4-5 is not salvation, but to receive power after the Holy Spirit has come upon you to be His witnesses through this power. This is what the word “filled” means. It refers to “overflowing”.
In John 20:22, Jesus having risen from the dead appeared to His disciples and breathed on them and said, “Receive the Holy Spirit”. This is when the disciples got born again. He breathed this new life into their spirit. Then right before ascending into heaven in Acts chapter 1 He tells them to wait in Jerusalem until they receive the Promise of the Father, being empowered to be His witnesses as they are filled (overflowing) with the Spirit that would come “up on” them. He was already in them.
Any church that does not teach in this Promise and actively see this in their church is denying one of the most important elements for believers. There were 120 in that upper room, and they were “all filled” with the Spirit and the evidence of speaking in tongues. Peter went on to preach in Acts chapter 2 this promise is for all. This initial yielding to the baptism of the Holy Spirit is how a believer begins to learn to yield to this power so that they can do the same works Jesus did as Jesus stated we could do in John 14:12. A healthy church teaches people to receive this power.