What is the root cause of unbelief?

Unbelief arises from the natural condition of humanity, which is characterized by a 'stony heart' that resists faith in God. In the sermon, it is explained that we inherit this tendency from our forefather Adam, making unbelief an automatic response of the flesh. Hebrews 3 warns of hardened hearts due to the deceitfulness of sin, indicating that apart from divine intervention, humans consistently depart from God. This inherent wickedness leads us to trust in our own understanding rather than God’s promises, illustrating the profound need for regeneration.