John 3:12

12 I have spoken to you of earthly things and you do not believe; how then will you believe if I speak of heavenly things?

John 3:12 in Other Translations

KJV
12 If I have told you earthly things, and ye believe not, how shall ye believe, if I tell you of heavenly things?
ESV
12 If I have told you earthly things and you do not believe, how can you believe if I tell you heavenly things?
NLT
12 But if you don’t believe me when I tell you about earthly things, how can you possibly believe if I tell you about heavenly things?
MSG
12 If I tell you things that are plain as the hand before your face and you don't believe me, what use is there in telling you of things you can't see, the things of God?
CSB
12 If I have told you about things that happen on earth and you don't believe, how will you believe if I tell you about things of heaven?

John 3:12 Meaning and Commentary

John 3:12

If I have told you earthly things
Not that the doctrines he delivered were earthly ones; for he was not of the earth, but from heaven, and above all, and so spake not of the earth, but of heaven, ( John 3:31 ) ; and this doctrine of regeneration was an heavenly doctrine; and the thing itself required supernatural power, and grace from above: but either they were the more easy doctrines of the Gospel; or were delivered in a plain and easy style, and illustrated by similes taken from earthly things, as from human birth, from the water, and from the wind:

and ye believe not;
i.e. those things; ye do not receive them, nor give credit to them; or "me", as the Ethiopic Version adds, who relate them on the best evidence, having fully known, and clearly seen them:

how shall ye believe;
give credit to me, or receive my testimony:

if I tell you of heavenly things?
of the more sublime doctrines of the Gospel, such as the descent of the Messiah from heaven; the union of the two natures, human and divine, in him; his being the only begotten Son of God; his crucifixion and death, signified by the lifting up of the serpent on a pole in the wilderness; and the wonderful love of God to the Gentile world in giving Christ to, and for them; and the salvation, and eternal happiness of all that believe in him, whether they be Jews or Gentiles; and these delivered in language suitable to them, without figures, or natural similes, which help the understanding, and convey ideas of things more easily to it.

John 3:12 In-Context

10 “You are Israel’s teacher,” said Jesus, “and do you not understand these things?
11 Very truly I tell you, we speak of what we know, and we testify to what we have seen, but still you people do not accept our testimony.
12 I have spoken to you of earthly things and you do not believe; how then will you believe if I speak of heavenly things?
13 No one has ever gone into heaven except the one who came from heaven—the Son of Man.
14 Just as Moses lifted up the snake in the wilderness, so the Son of Man must be lifted up,