Hebrews 6:13

For when God made His promise to Abraham, He took an oath by Himself, since He had no one greater by whom He could take it,

Hebrews 3:18

To whom did He take oath that they should not be admitted to His rest, if it was not to those who disobeyed Him?

Hebrews 6:18

so that by these two unchangeable things in which it is impossible for God to prove false, we who have taken refuge with Him may have encouragement strong enough to make us seize upon the hope that lies ahead of us.

Treasury of Scripture Knowledge

Summary

Therefore hear ye the word of the LORD, all Judah that dwell in the land of Egypt; Behold, I have sworn by my great name, saith the LORD, that my name shall no more be named in the mouth of any man of Judah in all the land of Egypt, saying, The Lord GOD liveth.

I have sworn

Bible References

I have sworn

Hebrews 3:18
To whom did He take oath that they should not be admitted to His rest, if it was not to those who disobeyed Him?
Hebrews 6:13
For when God made His promise to Abraham, He took an oath by Himself, since He had no one greater by whom He could take it,