Pentecost: Call on the Name of the Lord

To explain the outpouring of the Spirit on the day of Pentecost, Peter says that it is the fulfillment of what was prophesied in Joel 2. But also what is applied from the prophet Joel are the themes of judgment and repentance. So Peter exhorts his audience--as did Joel in the past, and as Paul will in the future--to "call on the name of the Lord" in repentance and faith to be saved.