What is the unforgivable sin?

According to the sermon, the unforgivable sin is blasphemy against the Holy Spirit. This sin involves rejecting the Holy Spirit's work and access in our lives, particularly refusing to accept God's gift of salvation through Him. The sermon explains that every other sin can be forgiven, but blasphemy against the Holy Spirit is eternal and cannot be forgiven because it is a complete rejection of God's means of salvation and forgiveness. The key point is that to reject the Holy Spirit is to deny God's gift of salvation, making it the only sin that leads to eternal separation from forgiveness and reconciliation with God.

For more details, see [36:11] and [40:00].