For God so loved the world, that he gave his one and only Son, that whoever believes in him should not perish, but have eternal life.

 John took that old story and used it as a kind of parable of Jesus. He says: "The serpent was lifted up; men looked at it; their thoughts were turned to God; and by the power of that god in whom they trusted they were healed. Even so Jesus must be lifted up; and when men turn their thoughts to him, and believe in him, they too will find eternal life." 