Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do?
Pricked in their heart? Who pricked their heart? Did they prick their own heart? Or did God prick their heart? The answers are no, they did not prick their own heart, God is the one Who did it. And the only reason they were pricked in their heart is because God took out their heart of stone and gave them a heart of flesh (Ezekiel 36:26). Hearts of stone feel nothing. And the reason He gave them a heart of flesh is because they were chosen in Christ before the foundation of the world (Ephesians 1:4). God gives His people a heart to know Him (Jeremiah 24:7) and fear Him for their own good and for the good of their children (Jeremiah 32:39). He opens some hearts and doesn’t open others (Acts 16:14). God turns hearts to hate His people, whether they be children of Israel or Christians (Psalm 105:25). And He does all of this while making some men believe they have free will!
Were ALL pricked in their heart? Maybe all of those present had their heart pricked that particular day when Peter preached, but are all men pricked in the heart when they hear the message? Obviously not. Again, it is God who pricks the hearts of men with the Gospel and He doesn’t prick every man’s heart just as He doesn’t call every man to salvation (1 Corinthians 1:26). And those He calls, He also justifies and glorifies (Romans 8:29-30), they aren’t given a choice. As a matter of fact, not every man even has a chance to hear the Gospel as thousands die every day without hearing it - and many solely because of where they live. But it was God who determined when and where they would live (Acts 17:26) so whether we like it or not, God determines whether a man will hear the Gospel or not. However, the sad truth is that every one who dies without Jesus is going to Hell whether they had an opportunity to hear the Gospel or not.
But the point of this Bible Truth is that these men were pricked in their heart and only then did they realize they were sinners and that God was drawing them - and those the Father draws, Jesus WILL raise up, no ifs, ands, or buts (John 6:44).