If I have told you earthly things and you do not believe, how will you believe if I tell you heavenly things?
John 3:12
Surrounding context
3:11 Most assuredly, I say to you, We speak what We know and testify what We have seen, and you do not receive Our witness.
3:12 If I have told you earthly things and you do not believe, how will you believe if I tell you heavenly things?
3:13 No one has ascended to heaven but He who came down from heaven, that is, the Son of Man who is in heaven.