Nicodemus, a Jewish scholar, a leader of Israel, comes to Jesus secretly, at night. He is burdened with a realization of his sin. He sees that all his efforts may be to no effect. What hope might Jesus have for him? In their discussion Jesus shows Nicodemus again and again that he is not able to understand the workings of God. God doesn't work according to Nicodemus' plan, but according to his own plan. He does not work salvation in the way we might devise. He works it in his own way. And look how he works it out.
You thought I would move to verse 16, right? But look at verses 14-15 instead. "And as Moses lifted up the serpent in the wildnerness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life" (ESV). Recall the serpent in the wilderness, a bronze version of the live serpents which were killing people of Israel, lifted up on a pole so that whoever looked to the image and believed God would provide rescue from the venomous creatures would live. Likewise, Jesus, very man and very God, is raised up on a pole, taking our sin, that which is venomous to us, and becomes the one who saves us. How does he save us? By our looking at him in faith we are saved. Salvation is of God. It is not through a means we would choose. It is through God's means. As he goes on to say in verse 16, "God loved the world in this way..." (personal translation). The word normally translated as "so" is an adverb. It indicates the way in which someone does something, not the extent to which he does something.
This is how God loved the world. He provided salvation by grace through faith, on his own terms, not the way we would devise.
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