The Bronze Serpent (or snake, also known as Nehushtan) was an object cast in the form of a snake that Moses made during Israel 's wandering in the desert of Sinai. Israel complained against God and Moses in the desert, wishing to return to Egypt. As a result, God sent venomous snakes to punish the Israelites and God had Moses craft a metal serpent, which would remedy the snake's venom when it was looked upon. For some time the Bronze Serpent was worshipped as an idol, until King Hezekiah of Judah destroyed it in his third year of rule. During Jesus Christ ministry, Jesus compared the Bronze Serpent to himself, classifying it as a type of Christ.
Serpents in the Desert
During Israel's time as nomad nation, they traveled by the Red Sea to avoid Edom on their way to Midian, because Edom had refused passage. The lengthy journey brought out the tireless nature of the Israelites, who complained about Moses and God. Israel expressed that they wished to return to Egypt, where food was easy to obtain and plentiful. By doing this, the Israelites were deeply testing God.
In response, God sent venomous snakes amongst the Israelites, causing many to die. The people then repented from their sin and asked Moses to intercede on their behalf to stop the snakes. So,when Moses prayed to God, he was instructed to make a model snake and attach it to a pole. Moses crafted the serpent out of bronze and attached it to a pole. Anyone who was bitten by the snakes that looked upon the Bronze Serpent would survive their venom. Thus, God provided salvation for Israel in the desert from the serpents he had sent.
Apparently the Serpent was held onto for some time after the Israelites were wandering in the desert. It is likely that the plague of venomous snake was not at a one time incident, but a continuous curse throughout Israel's wandering. After the cast snake was no longer needed, the Israelites retained it.
Worship as an Idol
At one point in time, the Israelites gave offerings to the Bronze Serpent and called it Nehushtan. Within Hezekiah's first three years of his reign, he shattered the Nehushtan into pieces. This effectively destroyed the Bronze Serpent and permanently ended false worship of it as an idol.
Son of Man Lifted Up
During Jesus' ministry, he likened himself to the Bronze Serpent, thus qualifying it as a type of Christ. Nicodemus approached Jesus under the auspices of the night and asked him how eternal life was achieved. Jesus responded with a monologue where he gave a simile: in the same way that Moses "raised up" the Bronze Serpent, he (the Son of Man) had to be lifted up; in order that believers in him would have eternal life.
The snake was both literally and figuratively raised up. Whoever looked upon the snake (thus trusting the snake, or the God behind the snake) to would not die from the bite of a venomous snake, similarly those who believed in Jesus Christ would not die, eternally.
Later, Jesus tells people that when he is "lifted up", then his equality with Father God would be recongized. This statement from Jesus is not directly connected to the Bronze Serpent; however, the original idiom was developed from a comparison of the snake.
Once again Jesus made a statement that would be lifted up, but did not connect it with the snake. He foretold that when he was lifted up all men would be drawn to him (an expansion of his original idiom). John notes that Jesus made this statements in order to foretell the type of death he would experience. This would qualify Jesus' original idiom as not only a figurative "raising", but a literal raising via crucifixion.
Types from the Past
In First Corinthians, Paul indirectly referenced the bronze serpent. In describing the examples of evil in Israel (types) of Israel's past, Paul tells his readers to not test Christ, like the Israelites did; who then as consequence were punished by serpents. This gives insight that is not presented in the original account: the Israelites were not only complaining in the wilderness, but testing God or Christ. This also marks the incident of the Bronze Serpent as a Biblical archetype for testing God.