The fiery serpent was a bronze snake figure that Moses made to heal the Israelites. When the people of Israel complained against God and Moses during their journey through the wilderness, God sent poisonous snakes as punishment. Many of the Israelites died from the snake bites (Numbers 21:4–9).
The people admitted their sin and asked Moses to pray for them. God told Moses to make a fiery (bronze) snake and put it on a pole. Anyone who was bitten could look at the bronze snake and be healed.
to this story when explaining his coming death. He said that just as Moses lifted up the snake in the wilderness, he would be lifted up (on the cross), and everyone who believes in him would have eternal life (John 3:14–15). The apostle Paul also used this story as a warning to Christians not to test God as the Israelites did (1 Corinthians 10:9).