Hebrews 6:13

For God, when making a promise to Abraham, since He had no one greater by whom to swear, swore by Himself,

Hebrews 3:18

And to whom did He swear, that they should not enter into His rest, but to those who were disbelieving?

Hebrews 6:17

wherein God, more abundantly willing to show to the heirs of the promise the immutability of His counsel, interposed with an oath;

Treasury of Scripture Knowledge

Summary

But if ye will not hear these words, I swear by myself, saith the LORD, that this house shall become a desolation.

Bible References

I

Hebrews 3:18
And to whom did He swear, that they should not enter into His rest, but to those who were disbelieving?
Hebrews 6:13
For God, when making a promise to Abraham, since He had no one greater by whom to swear, swore by Himself,