Jesus said to him (Thomas), I am the way, the truth, and the life. No-one comes to the Father except through me.
Jesus is the way. In the garden of Eden Adam and Eve lived in perfect harmony with God. They enjoyed His rich blessing without anything overshadowing it. But that happy relationship was destroyed by sin. Access to God was barred henceforth, for association between the God of all holiness and sinful man is impossible. But Jesus Christ came to open up the way to God for us. He died on the cross for sins (cf. 1 Peter 3:18).
Jesus is the truth. When Satan appeared in the garden of Eden in the form of a cunning serpent, he persuaded the couple to believe his lie that no danger was involved in being disobedient: God’s threat of judgment would not materialize. At the cross of Calvary, however, the truth came clearly to light. When Christ bore the judgment that sinners deserved, He proved that God cannot simply overlook sin. God’s holiness demands the punishment of disobedience and all evil.
Jesus is the life. Satan led Adam to disobey; consequently everybody was drawn into death: “Through one man sin entered the world, and death through sin, and thus death spread to all men, because all sinned” (Romans 5:12). But through His atoning sacrifice at the cross Jesus Christ frees every believer from death; but the gift of God is eternal life. “For the wages of sin is death; but the gift of God is eternal life in Christ Jesus our Lord” (Romans 6:23).
Image: By Selbymay – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=24358103