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12If I told you earthly things and you don`t believe, how will you believe if I tell you heavenly things? 13No one has ascended into heaven, but he who descended out of heaven, the Son of Man, who is in heaven. 14As Moses lifted up the serpent in the wilderness, even so must the Son of Man be lifted up, 15that whoever believes in him should not perish, but have eternal life.
John 3:12-16 (WEB)