John 3:33

He that has received his testimony has solemnly declared that God is true.

John 6:27

Labor not for the food that perishes, but for the food that endures to life eternal, which the Son of man will give you; for him has God the Father at tested.

Romans 3:3-4

What, indeed, if some have been unfaithful? Will their unfaithfulness overthrow the faithfulness of God?

Romans 4:18-21

He, against hope, confidently believed that he would become the father of many nations, according to that which was spoken: So shall your posterity be.

2 Corinthians 1:18

But God is true; for our preaching to you was not yes and no:

2 Corinthians 1:22

who has also set his seal upon us, and given us the earnest of the Spirit in our hearts.

Ephesians 1:13

in whom you also hoped after you heard the word of truth, the gospel of your salvation: in whom, after you also believed, you were sealed with the Holy Spirit of promise,

Titus 1:1-2

PAUL, a servant of God, and an apostle of Jesus Christ, according to the faith of God's elect, and the acknowledgement of the truth, which is according to godliness;

Hebrews 6:17

Wherefore, God, being more abundantly willing to show to the heirs of his promise the immutability of his purpose, inter posed an oath,

1 John 5:9-10

If we receive the testimony of men, the testimony of God is greater: for this is the testimony of God, which he has borne concerning his Son.

Revelation 7:3-8

saying: Hurt not the earth, nor the sea, nor the trees, till we have sealed the servants of our God on their foreheads.

Treasury of Scripture Knowledge

Summary

He that hath received his testimony hath set to his seal that God is true.

Bible References

Hath set

Romans 3:3
What, indeed, if some have been unfaithful? Will their unfaithfulness overthrow the faithfulness of God?
Romans 4:18
He, against hope, confidently believed that he would become the father of many nations, according to that which was spoken: So shall your posterity be.
2 Corinthians 1:18
But God is true; for our preaching to you was not yes and no:
Titus 1:1
PAUL, a servant of God, and an apostle of Jesus Christ, according to the faith of God's elect, and the acknowledgement of the truth, which is according to godliness;
Hebrews 6:17
Wherefore, God, being more abundantly willing to show to the heirs of his promise the immutability of his purpose, inter posed an oath,
1 John 5:9
If we receive the testimony of men, the testimony of God is greater: for this is the testimony of God, which he has borne concerning his Son.