I was thinking about the context of John 3:16. Jesus is telling Nicodemus of how Moses lifted up the serpent in the wilderness (see Numbers 21) and comparing Himself to that bronze serpent, which if the people looked upon they were healed.
Why did the people need healing? Because they had sinned against God and God had sent serpents among them to bite them and to slay them. The people were under God's judgement, but as an expression of mercy God told Moses to make a bronze serpent and caused that anyone who looked upon that serpent would be healed.
What did it mean for an Israelite, bitten by a serpent, to look upon that bronze serpent? It meant acknowledging that he or she had sinned against God and that he or she needed the mercy of God in order to be healed. It meant BELIEVING that looking upon that serpent would be efficacious in their healing.
In the same way, JESUS was lifted up because we have sinned and are under the judgement of God. We are all bitten by the serpent. We are all slowly perishing. But one look at Jesus, believing that He is efficacious to take away the poison and save us from death, and we too will be healed. We too shall be saved.
Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved. (Acts 4:12)
Much love to you all!