14 And as Moses lifted up the serpent in the wilderness, even so must the Son of Man be lifted up, 15 that whoever believes in Him should not perish but have eternal life. 16 For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life. 17 For God did not send His Son into the world to condemn the world, but that the world through Him might be saved.
18 “He who believes in Him is not condemned; but he who does not believe is condemned already, because he has not believed in the name of the only begotten Son of God. 19 And this is the condemnation, that the light has come into the world, and men loved darkness rather than light, because their deeds were evil. 20 For everyone practicing evil hates the light and does not come to the light, lest his deeds should be exposed.
When the Israelites were disobedient and complained about Moses leading them into the wilderness, and then their complaint turned toward God, and God responded. The response from the Lord was punishment for their sin. Serpents were sent among them and many died. But as it always is the Lord showed grace, and Moses was told to make a serpent of bronze and and place it on a pole,when the people were bitten if they looked on the bronze serpent they were healed.
It is that way with the Lord, if you look to Jesus who was placed on a pole (the Cross), then there is healing from the sin that has separated was from our loving God.
Just as we are reminded by John, "If we believe in all that Jesus did for us on the Cross then we are no longer condemned! The Apostle Paul amplified this when he declared, "Romans 8:1 There is therefore now no condemnation to those who are in Christ Jesus, who do not walk according to the flesh, but according to the Spirit."