Thy word is a lamp unto my feet, and light unto my path (Ps 119:105 ASV). When we understand and use God’s word properly it becomes our source of light for seeing the truth.
God’s word is like each foot having a lamp on it. The path in front of us is illuminated by the lights on our feet. Each step we take in life is illuminated by Gods word.
Some of us refuse to believe in God or that Jesus is God’s Son. In Luke it says, "Watch out that the light in you is not darkness” (Luke 11:35 NASU).
It takes a born again conversion of our lives for us to see clearly.