John 3:11-15

Truly, truly, I say to you, we speak of what we know and testify of what we have seen, and you do not accept our testimony. If I told you earthly things and you do not believe, how will you believe if I tell you heavenly things? No one has ascended into heaven, but He who descended from heaven: the Son of Man. As Moses lifted up the serpent in the wilderness, even so must the Son of Man be lifted up; so that whoever believes will in Him have eternal life.