Summary: The symbolism of the serpent on the pole, and the awful reality of the Man upon the Cross.
A SERPENT ON A POLE, AND A MAN ON A CROSS
Much of the books of Exodus and Numbers tells the sad history of a people who for forty years - whilst being delivered, led, and provided for by God - made a profession of complaining. The turning point came when a pole was raised up in the desert with a symbol of the enemy upon it (Numbers 21:8). There and then a generation of wilderness wanderers were called to grow up, cease their constant complaining, enter into the faith of Abraham (Galatians 3:9), and hasten on their journey towards the fulfillment of the promises.
The symbolism of the serpent on a pole was taken up by Jesus (John 3:14-15). Sin died at Calvary (2 Corinthians 5:21) - and death died, the wages of sin (Romans 6:23). All who fix their eyes upon Jesus (Hebrews 12:1-2), trusting in His finished work upon the Cross, enter into a new state of being called “eternal life” (John 3:16).
“Just as Moses lifted up the snake in the desert, so the Son of Man must be lifted up, so that everyone who believes in him may have eternal life. For God so loved the world that he gave His one and only Son, so 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” (John 3:14-17).
If a serpent on a pole was a shocking symbol for a monotheistic people, so is the picture in our minds’ eye of the broken body of a man impaled upon a wooden cross. Yet, in both instances, this is what God commanded. Without the brazen serpent there was no healing for the Israelite who had been bitten by a snake (Numbers 21:9) - and without the Cross there is no salvation for any one of us, bitten as we are by the sting of death which is sin (1 Corinthians 15:55-57).
Jesus was “lifted up” in the crucifixion, so that everyone who believes in Him, trusting not in themselves but trusting in His sacrificial blood, would have eternal life. This was, and is, the supreme act of God’s love.
Our God is the God of the unusual. Looking at the symbol He has commanded brought healing to the poisoned Israelite, and similarly brings salvation to the would-be Christian. There is no time for prevarication: do this or die.