Hebrews 6:13 in the World English Bible
For when God made a promise to Abraham, since he could swear by no one greater, he swore by himself,
Context
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.