How do we know that God can change a person's heart?

The evidence of God's ability to change a person's heart is powerfully illustrated in the narrative of Saul's conversion in Acts 9. God intervened in Saul's life while he was actively opposing the Church. This raises the essential truth that it is not our efforts but God's sovereign grace that brings about true conversion. Throughout the Bible, we see that the Holy Spirit convicts, regenerates, and draws individuals to Himself, enabling them to turn from their sin and follow Christ. This is affirmed in scriptures such as Ephesians 2:1-5, which speaks to our previous state of spiritual deadness and God's mercy in making us alive in Christ. The life-changing power of God is not limited to biblical figures but extends to all who have been transformed by His grace.