And just as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life.

Christ says “just as” so we can learn something about our salvation from the analogy he makes.  The event is related in Numbers 21.4-9.  The people spoke against God and Moses because they “became impatient on the way.”  They complained about no food and water and said they detested the food they were given.  So the Lord sent poisonous serpents among the people to bite them and many died.  The people repented so the Lord told Moses “Make a poisonous serpent, and set it on a pole; and everyone who is bitten shall look at it and live.”  So he made a serpent of bronze and put it on a pole and anyone who became bitten would look at the serpent and live.  This was a historical even which wonderfully anticipated the great salvific action of the Incarnation and Passion.

We are all sinners, there are none of us who aren’t.  And sin is its own punishment.  The instrument of life and healing for the Israelites was the same instrument by which they were punished.  And so “he who knew no sin was made sin for us.”  Christ became sin for us so that we who are stung by sin may look upon he who became sin, believe and live – not just earthly life but eternal life.  Yes, we are healed even now as the Israelites were, but because this time it is God’s Son, the healing he brings also opens the door to eternal life with him.  That is the incomprehensible depth of God’s love.  But once healed the Israelites may have been bitten again.  Even so, belief in Christ does not mean we no longer sin.  It means that when we do sin we now have Christ on the cross to gaze upon and believe in, and be healed and our life restored.