Those who believe that they believe in God, but without any passion in their heart, without anguish of mind, without uncertainty, without doubt, without an element of despair even in their consolation...
Mark 5:36, Psalm 34:4, Isaiah 41:10, Matthew 9:22, Philippians 4:6-7, Job 3:25
Medical literature is replete with case reports of patients dying, not from actual illness, but from believing they were sick, from the fear they were going to die.