Peter was going for broke. Standing with the Eleven on the Day of Pentecost, he said to the crowd, “Therefore let all the house of Israel know assuredly that God has made this Jesus, whom you crucified, both Lord and Christ” (Acts 2:36).
Talk about taking a risk. They could have killed Peter for saying that. I wonder if Peter thought, “Okay, maybe I cowered before the opinion of someone I didn’t even know by that fire in the courtyard, but those days are gone. I have new power now. I have the Holy Spirit permeating my life. And I’m going to tell the truth.”
To show you that his message was the right one, look at their reaction: “Now when they heard this, they were cut to the heart, and said to Peter and the rest of the apostles, ‘Men and brethren, what shall we do?’” (verse 37). This could be translated, “They were pierced to the heart.” This phrase appears only here in the New Testament, and it means “to pierce” or “stab.” Thus, it depicts something sudden and unexpected. It was the conviction of the Holy Spirit.
We all have been stabbed in the back, but have you ever been stabbed in the heart? It’s when someone says something to you that isn’t easy to hear. The reason it hurt is because they were right. It feels like a horrible thing, but it is a good thing. Don’t think of it as a sword killing you; think of it as a scalpel in the hand of a surgeon who’s saving your life and cutting the cancer out.
At Pentecost, the people were stabbed in the heart by the scalpel of the Holy Spirit. There was a sense inside that they needed to get right with God.