John 3:33
He that receiveth his testimony hath avouched that God is true.
John 6:27
Labour not for the meat which is perishable, but for that meat which endureth unto life eternal, which the Son of man will give you: for him hath the Father sealed, even God.
Romans 3:3-4
For what if some were unbelievers? shall their unbelief render the faithfulness of God ineffectual?
Romans 4:18-21
Who contrary to hope, in hope believed, that he should be the father of many nations, according to what was said, "So shall thy seed be."
2 Corinthians 1:18
But as sure as God is true, our word to you was not yea and nay.
2 Corinthians 1:22
who also hath put his seal upon us, and given us the earnest of the Spirit in our hearts.
Ephesians 1:13
In whom ye also [trusted] after ye had heard the word of truth, the gospel of your salvation; in whom also, having believed, ye have been 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 the elect of God, and the knowledge of truth which leads to godliness;
Hebrews 6:17
And thus God, designing more abundantly to demonstrate to the heirs of promise the immutability of his will, pledged himself by oath,
1 John 5:9-10
If we receive the testimony of man, the testimony of God is stronger: for this is the testimony of God which he testified concerning his Son.
Revelation 7:3-8
saying, Hurt not the earth, nor the sea, nor the trees, until we have sealed the servants of our God in their foreheads.