Hebrews 6:13 KJV
For when God made promise to Abraham, because he could swear by no greater, he sware by himself,
Hebrews 6:11–15 KJV Chapter Context
11
And we desire that every one of you do shew the same diligence to the full assurance of hope unto the end:
12
That ye be not slothful, but followers of them who through faith and patience inherit the promises.
13
For when God made promise to Abraham, because he could swear by no greater, he sware by himself,
14
Saying, Surely blessing I will bless thee, and multiplying I will multiply thee.
15
And so, after he had patiently endured, he obtained the promise.