Why can't the natural man hear the Gospel?

Scripture reveals that by nature, humanity is spiritually deaf and unable to understand or accept the truths of the Gospel. Romans 3:10-12 states that no one is righteous, no one understands, and no one seeks God. This spiritual blindness and deafness necessitates God's gracious intervention for someone to hear the good news of Christ. Just as the deaf man in Mark 7 could not hear until Jesus spoke the word 'Ephatha,' so must the Lord regenerate the hearts of the unresponsive to enable them to hear and believe (John 3:3). It underscores the need for divine grace to open our ears.