John 3:12

If I told you earthly things and you do not believe, how will you believe if I tell you heavenly things?

John 1:1-14

In the beginning was the Word, and the Word was with God, and the Word was God.

John 3:3

Jesus answered and said to him, “Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God.”

John 3:5

Jesus answered, “Truly, truly, I say to you, unless one is born of water and the Spirit he cannot enter into the kingdom of God.

John 3:8

The wind blows where it wishes and you hear the sound of it, but do not know where it comes from and where it is going; so is everyone who is born of the Spirit.”

John 3:13-17

No one has ascended into heaven, but He who descended from heaven: the Son of Man.

John 3:31-36

He who comes from above is above all, he who is of the earth is from the earth and speaks of the earth. He who comes from heaven is above all.

1 Corinthians 2:7-9

but we speak God’s wisdom in a mystery, the hidden wisdom which God predestined before the ages to our glory;

1 Corinthians 3:1-2

And I, brethren, could not speak to you as to spiritual men, but as to men of flesh, as to infants in Christ.

1 Timothy 3:16

By common confession, great is the mystery of godliness:
He who was revealed in the flesh,
Was vindicated in the Spirit,
Seen by angels,
Proclaimed among the nations,
Believed on in the world,
Taken up in glory.

Hebrews 5:11

Concerning him we have much to say, and it is hard to explain, since you have become dull of hearing.

1 Peter 2:1-3

Therefore, putting aside all malice and all deceit and hypocrisy and envy and all slander,

1 John 4:10

In this is love, not that we loved God, but that He loved us and sent His Son to be the propitiation for our sins.

Treasury of Scripture Knowledge

Summary

If I have told you earthly things, and ye believe not, how shall ye believe, if I tell you of heavenly things?

Bible References

Earthly

John 3:3
Jesus answered and said to him, “Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God.”
1 Corinthians 3:1
And I, brethren, could not speak to you as to spiritual men, but as to men of flesh, as to infants in Christ.
Hebrews 5:11
Concerning him we have much to say, and it is hard to explain, since you have become dull of hearing.
1 Peter 2:1
Therefore, putting aside all malice and all deceit and hypocrisy and envy and all slander,

Heavenly

John 3:13
No one has ascended into heaven, but He who descended from heaven: the Son of Man.
John 1:1
In the beginning was the Word, and the Word was with God, and the Word was God.
1 Corinthians 2:7
but we speak God’s wisdom in a mystery, the hidden wisdom which God predestined before the ages to our glory;
1 Timothy 3:16
By common confession, great is the mystery of godliness:
He who was revealed in the flesh,
Was vindicated in the Spirit,
Seen by angels,
Proclaimed among the nations,
Believed on in the world,
Taken up in glory.
1 John 4:10
In this is love, not that we loved God, but that He loved us and sent His Son to be the propitiation for our sins.