In John 3:1-21 Jesus is talking to Nicodemus. In John 3:14-15 Jesus says “Just as Moses lifted up the snake in the desert, so the Son of Man must be lifted up, that everyone who believes in him may have eternal life.”
This had to be confusing to an already confused Nicodemus. First he is saying I have to be born again, now He is talking about Moses and snakes. Just imagine the understanding he received after seeing Jesus on the cross and hearing of the resurrection.
In Numbers 21:4-9 we read about the bronze snake. As the Israelites were traveling through the desert they started to complain and speak out against God. They complained that while God was supplying for there needs, it wasn’t good enough. How often do we complain to God that we are not satisfied, even though he meets our every need?
God sent venomous snakes amongst them and many died from the bites. They confessed their sins and prayed that the LORD would take the snakes away. (Numbers 21:7)
God answered “The LORD said to Moses, ‘Make a snake and put it up on a pole; anyone who is bitten can look at it and live.” So Moses made a bronze snake and put it up on a pole. Then when anyone was bitten by a snake and looked at the bronze snake, he lived. (Numbers 21:8-9)
“Just as Moses lifted up the snake in the desert, so the Son of Man must be lifted up, that everyone who believes in him may have eternal life.” John 13:14-15
The Israelites were dying in their sin, just as we were dying in our sin. (Ephesians 2:1) If they looked upon the bronze snake on the pole they gained life. If we look at the sacrifice Jesus Christ made upon the cross, we gain life.
For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. For God did not send his Son into the world to condemn the world, but to save the world through him. Whoever believes in him is not condemned, but whoever does not believe stands condemned already because he has not believed in the name of God’s one and only Son. John 3:16-18