"4 From Mount Hor they set out by the way to the Red Sea, to go around the land of Edom. And the people became impatient on the way. 5 And the people spoke against God and against Moses, “Why have you brought us up out of Egypt to die in the wilderness? For there is no food and no water, and we loathe this worthless food.” 6 Then the Lord sent fiery serpents among the people, and they bit the people, so that many people of Israel died. 7 And the people came to Moses and said, “We have sinned, for we have spoken against the Lord and against you. Pray to the Lord, that he take away the serpents from us.” So Moses prayed for the people. 8 And the Lord said to Moses, “Make a fiery serpent and set it on a pole, and everyone who is bitten, when he sees it, shall live.” 9 So Moses made a bronze serpent and set it on a pole. And if a serpent bit anyone, he would look at the bronze serpent and live."
Numbers 21:4-9
This remarkable illustration teaches us something more about the nature of sin, however. The serpents were sent to Israel as a punishment for their murmurings against God. They were men in revolt. Sin, Jesus means to tell us, is revolt against God, against His good and perfect will. This can be seen clearly in the story of Nicodemus, who was blind to the truth about the new birth, as may be gathered from his comments. But it was a willing blindness: he did not want to see the truth, because seeing it would have been at that point much too costly a thing for him. He was resisting it because his heart was in rebellion against God, as the Israelites were. And it is important that we should see that this kind of fatal revolt can occur in people like Nicodemus as well as in the wayward, murmuring Israelites. As Paul puts it in Romans 8:5ff, they that are in the flesh cannot please God, being at enmity with Him and this is true whether the 'flesh' be respectable or religious, as well as gross or depraved. This truth is a bitter pill for the natural man to swallow, but swallow it he must, if he is to know anything of the blessing and the peace of God's salvation.