The reason many hear but are never able to truly understand is because their hearing is not combined with faith (Matthew 13:10-13; Hebrews 4:2). Faith comes when Christ’s voice becomes the only thing that we pay attention to (Romans 10:17).
Many Christians worship other “gods” along with Jesus. When we care for the approval of others because we love our reputation, we make “gods” out of people. Then, no matter how much we hear, we will never receive faith (John 5:41-44).
The one who comes to God must believe that He IS — which means that everyone/everything else ISN’T (Hebrews 11:5-6)! Enoch lived such a life for 300 years after he was warned about the coming judgment, and thereby received God’s approval (Genesis 5:21-24).
Enoch walked with God for 300 years and “was not” (physically). Jesus likewise walked with His Father for His entire life and “was not” of this earth (spiritually). This is the true life of faith that we also are called to live.