Jesus said "I AM" to reveal His divine identity as God and to show that He is the eternal, self-existent One. When Moses asked God for His name, God replied, "I AM THAT I AM" (Exodus 3:14, KJV). By using the same expression, Jesus identified Himself with the God who spoke to Moses. In John's Gospel, Jesus declared, "I am the bread of life," "I am the light of the world," "I am the good shepherd," "I am the resurrection, and the life," and "I am the way, the truth, and the life," revealing different aspects of His mission and character. Most strikingly, Jesus said, "Before Abraham was, I am" (John 8:58, KJV), a statement that His listeners understood as a claim to deity. Through these declarations, Jesus revealed that He is the promised Messiah, the Son of God, and the eternal Lord who alone gives life and salvation.
