“Therefore let all Israel be assured of this: God has made this Jesus, whom you crucified, both Lord and Christ.” When the people heard this, they were cut to the heart and said to Peter and the other apostles, “Brothers, what shall we do?”" - Acts 2:36-37
I cut my finger. Yes, I wasn't being careful and with a slip of the hand a very well sharpened knife sliced right into the little digit. I always make sure that my knives are sharp as razors and when they are properly used they are great tools. But this time, with a misguided flex of muscle, the blade literally "cut to the bone".
When Peter spoke the Word of God in the power and wisdom of the Holy Spirit, people responded. They were moved to conviction and knew a decision was needed. When the Scriptures are used with God empowered precision, they are "... living and active. Sharper than any double-edged sword..." (Hebrews 4:12) With a well guided flex of the Spirit, the Word will literally "cut to the heart".
Paul counseled Timothy in 2 Timothy 2:15 to do his best to rightly handle the Word of truth. Are you doing your best in the study of the Bible? Are you skilled in using it to bring truth to bear in your life and in the lives of others? Remember my friend, the Word of God is a sharp tool of spiritual value, intended to "cut to the heart".