What does the Bible say about believing on the Son of God?

John 9 recounts the story of a blind man who, upon gaining his sight, was asked by Jesus if he believed on the Son of God. True belief involves recognizing and accepting Jesus Christ as He has revealed Himself, not merely understanding theological concepts. This is reflected in John 17:3, which states that eternal life is knowing the only true God and Jesus Christ. To believe on Him signifies a relationship built on faith and trust, rather than an intellectual agreement with doctrines.