Numbers 21: 4-9
4 They traveled from Mount Hor along the route to the Red Sea, to go around Edom. But the people grew impatient on the way; 5 they spoke against God and against Moses, and said, “Why have you brought us up out of Egypt to die in the wilderness? There is no bread! There is no water! And we detest this miserable food!”6 Then the Lord sent venomous snakes among them; they bit the people and many Israelites died. 7 The people came to Moses and said, “We sinned when we spoke against the Lord and against you. Pray that the Lord will take the snakes away from us.” So Moses prayed for the people.8 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.” 9 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, they lived.
14 Just as Moses lifted up the snake in the wilderness, so the Son of Man must be lifted up, 15 that everyone who believes may have eternal life in him.”
16 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. 17 For God did not send his Son into the world to condemn the world, but to save the world through him. 18 Whoever believes in him is not condemned, but whoever does not believe stands condemned already because they have not believed in the name of God’s one and only Son. 19 This is the verdict: Light has come into the world, but people loved darkness instead of light because their deeds were evil. 20 Everyone who does evil hates the light, and will not come into the light for fear that their deeds will be exposed. 21 But whoever lives by the truth comes into the light, so that it may be seen plainly that what they have done has been done in the sight of God.