Psalm 119:152

I have long had knowledge that your unchanging word is for ever.

Luke 21:33

Heaven and earth will come to an end, but my words will not come to an end.

Psalm 89:34-37

I will be true to my agreement; the things which have gone out of my lips will not be changed.

Psalm 111:7-8

The works of his hands are faith and righteousness; all his laws are unchanging.

Psalm 119:144

The righteousness of your unchanging word is eternal; give me wisdom so that I may have life.

Psalm 119:160

Your word is true from the first; and your upright decision is unchanging for ever.

Ecclesiastes 3:14

I am certain that whatever God does will be for ever. No addition may be made to it, nothing may be taken from it; and God has done it so that man may be in fear before him.

Treasury of Scripture Knowledge

Summary

Concerning thy testimonies, I have known of old that thou hast founded them for ever.

Bible References

Thy testimonies

Psalm 119:144
The righteousness of your unchanging word is eternal; give me wisdom so that I may have life.
Psalm 89:34
I will be true to my agreement; the things which have gone out of my lips will not be changed.
Psalm 111:7
The works of his hands are faith and righteousness; all his laws are unchanging.
Ecclesiastes 3:14
I am certain that whatever God does will be for ever. No addition may be made to it, nothing may be taken from it; and God has done it so that man may be in fear before him.
Luke 21:33
Heaven and earth will come to an end, but my words will not come to an end.

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain