Hebrews 6:15-17

Young's Literal Translation

¹⁵ and so, having patiently endured, he did obtain the promise;

¹⁶ for men indeed do swear by the greater, and an end of all controversy to them for confirmation [is] the oath,

¹⁷ in which God, more abundantly willing to shew to the heirs of the promise the immutability of his counsel, did interpose by an oath,