Believing Jesus is God is no small matter. It goes to the heart of our hope as Christians–we trust in Jesus for the forgiveness of our sins! If Jesus isn’t God, there is no hope for sinners because no mere human could perfectly obey God’s law and sustain God’s infinite wrath against sin.
The Heidelberg Catechism, which for centuries has provided instruction and comfort for Christians, addresses the need for a mediator and deliverer who is not just a man but God himself. This is necessary “that he might, by the power of his Godhead sustain in his human nature, the burden of God’s wrath; and might obtain for, and restore to us, righteousness and life” (Heidelberg Catechism Q&A 17).
If it’s so important, why didn’t Jesus spell it out by saying, “I am God?” Though we can’t answer this question with certainty, I’m not sure we need to. Here are three places in the Gospel of John that Jesus clearly claims to be God:
1. Jesus claims to be the Son of Man.
In John 3, Nicodemus, a religious leader of the Jews, comes to Jesus inquiring about his teaching. Jesus tells him, “No one has ascended into heaven except he who descended from heaven, the Son of Man” (John 3:13) His point is that he can speak to Nicodemus about heavenly things because he himself has come down from heaven.
This title Jesus takes for himself–the Son of Man–is significant. In the Old Testament, this Son of Man is a heavenly figure who rules forever over his kingdom that will never be destroyed (Dan. 7:14). Throughout the Gospels, it emphasizes the incarnation–God taking human form. It’s important to note that in the very next breath, after claiming for himself the title Son of Man and thus claiming for himself heavenly origin and his coming eternal kingdom, Jesus turns and speaks of his coming crucifixion to give life to those who believe (John 3:14—15).
It’s because Jesus is God incarnate that his death can obtain life for those who believe in him.
2. Jesus claims to be one with the Father.
One winter day, Jesus was walking in the temple when he was surrounded by Jews asking him to spell it out for them: “How long will you keep us in suspense? If you are the Christ, tell us plainly” (John 10:24). They wanted to know if he was indeed the long-awaited Messiah, whom the Old Testament prophesied would be God (Isa. 7:14, Isa. 9:6, Mic. 5:2).
Jesus tells them that he has told them–through the works he has done. Jesus is the Good Shepherd who lays his life down for his sheep (John 10:1—18). His opponents don’t believe because they’re not his sheep. But his sheep receive eternal life from him because they hear his voice and follow him (John 10:25—29).
Then he spells it out for them: “I and the Father are one.”
Evidently, this claim was clear enough for the Jews pressing in around Jesus to pick up stones to kill him for blaspheming: “It is not for a good work that we are going to stone you but for blasphemy, because you, being a man, make yourself God” (John 10:31—33).
3. Jesus claims to be I AM.
This wasn’t Jesus’ first brush with the Pharisees that ended in attempted execution when he claimed to be God himself. In John 8, Jesus is accused of doing miracles through demonic power. He promises life to those who follow and obey him. This infuriates his opponents. They consider this an arrogant claim to be superior to the Jewish patriarch Abraham, since Abraham did die. Jesus says, “Your father Abraham rejoiced that he would see my day. He saw it and was glad” (John 8:56). The Jews say this is preposterous since Jesus is not yet 50 years old!
Jesus said to them, “Truly, truly, I say to you, before Abraham was, I am” (John 8:58).
I AM. Jesus was claiming the name the Lord God of Israel used for himself at the burning bush when he revealed himself to Moses. The one who said to Moses “I AM” revealed himself in yet another way to Moses:
“God also said to Moses, ‘Say this to the people of Israel: “The Lord, the God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you.”’ This is my name forever, and thus I am to be remembered throughout all generations” (Exod. 3:15).
This is who Jesus claimed to be. It was enough as far as the Jews were concerned: “So they picked up stones to throw at him, but Jesus hid himself and went out of the temple” (John 8:59).
Though Jesus never says “I am God” in so many words, he unmistakably identifies himself as God in astounding ways. In life-giving ways. Only God himself could do what was needed to reconcile us to himself and “restore to us righteousness and life.”
 There are many places in Scripture we might turn to consider the deity of Christ. The Old Testament prophesied that the coming Messiah would be divine (Isa. 7:14, Isa. 9:6, Mic. 5:2). The New Testament writers declare that Jesus is God (Rom. 9:5, Titus 2:13, Heb. 1:8). Divine attributes are given to Christ (John 5:22, Acts 17:31, Heb. 1:3, Col. 1:17). The Bible calls us to worship Christ as God (John 5:23, 1 Cor. 1:2, Phil. 2:9-11).
 For a longer discussion of why Jesus uses this title for himself, see Leon Morris, The Gospel According to John, The New International Commentary on the New Testament (Grand Rapids, MI: Wm. B. Eerdmans Publishing Co., 1995), 150-52.
 Jesus’ claim to be the Good Shepherd in John 10:1—18 fulfills the promise in Ezekiel 34 that God himself would rule as a good shepherd over his people. By claiming to be the good shepherd, Jesus claimed to be the promised divine king.
 Heidelberg Catechism Q&A 17