Acts 2:38 shows the response to Peter's sermon — repentance and baptism to receive the same Spirit promised by Joel.

Acts 1:5 records Jesus' promise of Spirit baptism — the very event Peter declares fulfilled here on Pentecost.

Joel 2:28-32 is the prophecy Peter quotes verbatim—the outpouring of the Spirit on all flesh, which he declares is being fulfilled at Pentecost.

Luke 4:18 shows Jesus reading Isaiah about the Spirit's anointing—a different fulfillment, but parallels Peter's claim that Spirit prophecy is now realized.

Ephesians 1:13 describes believers being sealed with the promised Holy Spirit — the same Spirit outpoured in Acts 2.