How do we know that only the elect will believe in the gospel?

The assurance that only the elect will believe the gospel comes from Scripture, particularly in John 10:26-27, where Jesus states, 'You do not believe because you are not my sheep. My sheep hear my voice, and I know them, and they follow me.' This highlights a clear distinction: those not chosen by God will neither hear nor respond to the gospel message. The gospel's effectiveness lies in its divine origin and its power, as it is delivered through the Holy Spirit to those whom God has elected. Therefore, the belief is a result of God's sovereign choice and empowering grace, turning hearts towards Him.