How do we know that true holiness is produced by the Holy Spirit?

The assurance that true holiness is a product of the Holy Spirit can be drawn from the transformative nature of the gospel. When the great trumpet of jubilee proclaims the liberating power of God's grace, believers respond with spiritual affections and desires that were previously unattainable. The Spirit of God fundamentally alters a believer's heart, enabling them to worship authentically and in truth. This holiness fosters spiritual insights and fosters a genuine relationship with God, distinguishing it from a mere legalistic approach to piety. As emphasized in the writings of historic Reformed theology, holiness cannot be manufactured through human effort but is wholly dependent on divine grace through the work of the Spirit.