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. 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.” Then the LORD sent fiery serpents among the people, and they bit the people, so that many people of Israel died. 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. 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.” 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 ESV)

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 The wind blows where it wishes, and you hear its sound, but you do not know where it comes from or where it goes. So it is with everyone who is born of the Spirit.”

Nicodemus said to him, “How can these things be?” Jesus answered him, “Are you the teacher of Israel and yet you do not understand these things? Truly, truly, I say to you, we speak of what we know, and bear witness to what we have seen, but you do not receive our testimony. If I have told you earthly things and you do not believe, how can you believe if I tell you heavenly things? No one has ascended into heaven except he who descended from heaven, the Son of Man. And as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life. (John 3:8-15 ESV)