Hebrews 6:16-20

16For people swear by something greater than themselves, and the oath serves as a confirmation to end all dispute.

17In the same way God wanted to demonstrate more clearly to the heirs of the promise that his purpose was unchangeable, and so he intervened with an oath,

18so that we who have found refuge in him may find strong encouragement to hold fast to the hope set before us through two unchangeable things, since it is impossible for God to lie.

19We have this hope as an anchor for the soul, sure and steadfast, which reaches inside behind the curtain,

20where Jesus our forerunner entered on our behalf, since he became a priest forever in the order of Melchizedek.